diff --git a/audio-compressor/index.html b/audio-compressor/index.html
index 29aed3c..1366f09 100644
--- a/audio-compressor/index.html
+++ b/audio-compressor/index.html
@@ -13,9 +13,9 @@
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       gtag('config', 'G-62ZJNZFRES');
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-    <title>Audio Compressor — Reduce File Size Free | AudioTools.dev</title>
-    <meta name="description" content="Compress audio files online for free. Reduce MP3, WAV file size by adjusting bitrate and sample rate. No upload, runs in your browser.">
-    <meta name="keywords" content="audio compressor, reduce audio file size, compress mp3 online, shrink audio file, audio bitrate reducer, compress wav free">
+    <title>Compress MP3 &amp; Audio Files Online, Free | AudioTools.dev</title>
+    <meta name="description" content="Make audio files smaller for email or chat. Pick a bitrate, see the new size first, compress one file or a batch. Free, no upload, runs in your browser.">
+    <meta name="keywords" content="compress mp3, reduce audio file size, audio compressor, make audio file smaller, compress audio for email, mp3 compressor online, compress wav to mp3">
     <link rel="canonical" href="https://audiotools.dev/audio-compressor/">
     <link rel="alternate" hreflang="en" href="https://audiotools.dev/audio-compressor/">
     <link rel="alternate" hreflang="zh" href="https://audiotools.dev/zh/audio-compressor/">
@@ -24,22 +24,22 @@
     <meta property="og:site_name" content="AudioTools.dev">
     <meta property="og:locale" content="en_US">
     <meta property="og:url" content="https://audiotools.dev/audio-compressor/">
-    <meta property="og:title" content="Audio Compressor — Reduce File Size Free | AudioTools">
-    <meta property="og:description" content="Compress audio files online for free. Reduce MP3, WAV file size by adjusting bitrate and sample rate. No upload, runs in your browser.">
+    <meta property="og:title" content="Compress MP3 &amp; Audio Files Online, Free">
+    <meta property="og:description" content="Make audio files smaller for email or chat. Pick a bitrate, see the new size first, compress one file or a batch. Free, no upload, runs in your browser.">
     <meta property="og:image" content="https://audiotools.dev/og/audio-compressor.png">
     <meta property="og:image:width" content="1200">
     <meta property="og:image:height" content="630">
-    <meta property="og:image:alt" content="Audio Compressor — Reduce File Size Free | AudioTools">
+    <meta property="og:image:alt" content="Compress MP3 &amp; Audio Files Online, Free">
     <meta name="twitter:card" content="summary_large_image">
-    <meta name="twitter:title" content="Audio Compressor — Reduce File Size Free | AudioTools">
-    <meta name="twitter:description" content="Compress audio files online for free. Reduce MP3, WAV file size by adjusting bitrate and sample rate. No upload, runs in your browser.">
+    <meta name="twitter:title" content="Compress MP3 &amp; Audio Files Online, Free">
+    <meta name="twitter:description" content="Make audio files smaller for email or chat. Pick a bitrate, see the new size first, compress one file or a batch. Free, no upload, runs in your browser.">
     <meta name="twitter:image" content="https://audiotools.dev/og/audio-compressor.png">
     <meta name="robots" content="index, follow, max-snippet:-1, max-image-preview:large">
     <link rel="icon" type="image/svg+xml" href="/favicon.svg">
     <link rel="icon" type="image/x-icon" href="/favicon.ico">
     <link rel="apple-touch-icon" href="/apple-touch-icon.png">
     <script type="application/ld+json">
-    {"@context":"https://schema.org","@type":"WebApplication","name":"Audio Compressor — AudioTools.dev","url":"https://audiotools.dev/audio-compressor/","description":"Compress audio files online for free. Reduce MP3, WAV file size by adjusting bitrate and sample rate. No upload, runs in your browser.","applicationCategory":"MultimediaApplication","operatingSystem":"Any","isAccessibleForFree":true,"offers":{"@type":"Offer","price":"0","priceCurrency":"USD"}}
+    {"@context":"https://schema.org","@type":"WebApplication","name":"Audio Compressor — AudioTools.dev","url":"https://audiotools.dev/audio-compressor/","description":"Make audio files smaller for email or chat. Pick a bitrate, see the new size first, compress one file or a batch. Free, no upload, runs in your browser.","applicationCategory":"MultimediaApplication","operatingSystem":"Any","isAccessibleForFree":true,"offers":{"@type":"Offer","price":"0","priceCurrency":"USD"}}
     </script>
     <script type="application/ld+json">
     {
@@ -48,10 +48,18 @@
         "mainEntity": [
             {
                 "@type": "Question",
-                "name": "How much can I reduce file size?",
+                "name": "How do I reduce the size of an MP3 file?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "Depending on the source, you can reduce WAV files by 5–20x by converting to MP3. A 50 MB WAV becomes ~5 MB at 128 kbps."
+                    "text": "Re-encode it at a lower bitrate. Drop the MP3 here, pick 128 kbps or 64 kbps, and download the smaller file. Lowering the sample rate to 22050 Hz shrinks voice recordings further."
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "How much smaller will my file be?",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "About 1 MB per minute at 128 kbps and 0.5 MB per minute at 64 kbps. A WAV file usually becomes 5 to 20 times smaller. The tool shows the estimate before you compress."
                 }
             },
             {
@@ -59,7 +67,7 @@
                 "name": "Does compression affect quality?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "Lossy compression removes some data. At 192 kbps or higher, most listeners cannot tell the difference from the original."
+                    "text": "Lossy compression removes some data. At 192 kbps or higher, most listeners cannot tell the difference from the original; for speech, 64 kbps is enough."
                 }
             },
             {
@@ -70,12 +78,20 @@
                     "text": "Yes. Drop several files: all of them are compressed with the same settings, and you can download each one or all of them as a ZIP."
                 }
             },
+            {
+                "@type": "Question",
+                "name": "Which sample rate should I use for voice?",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "22050 Hz keeps speech clear and makes the file smaller. 16000 Hz is the smallest and still fine for speech, but not for music."
+                }
+            },
             {
                 "@type": "Question",
                 "name": "Is my audio uploaded?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "No. All compression happens in your browser using the Web Audio API."
+                    "text": "No. All compression happens in your browser."
                 }
             }
         ]
@@ -153,8 +169,8 @@
     <div class="container">
         <section class="hero">
             <svg class="hero-glyph" viewBox="0 0 160 56" aria-hidden="true"><polyline class="g-ink" style="stroke-width:1.6" points="4,28 7,14 10,40 13,18 16,36 19,10 22,44 25,20 28,34 31,12 34,42 37,22 40,30 43,16 46,38 49,24 52,32 55,20 58,28"/><polyline class="g-acc" points="72,28 88,14 104,40 120,16 136,38 152,24 156,28"/></svg>
-            <h1>Audio Compressor</h1>
-            <p>Reduce audio file size by adjusting bitrate and sample rate — output as MP3, no upload</p>
+            <h1>Compress Audio Files</h1>
+            <p>Make MP3, WAV and other audio files smaller — choose the bitrate, see the size first, no upload</p>
         </section>
 
         <div class="tool-area">
@@ -226,21 +242,39 @@ <h1>Audio Compressor</h1>
         </div>
 
         <section class="seo-content">
-            <h2>Free Online Audio Compressor</h2>
-            <p>Audio Compressor reduces the file size of your audio by re-encoding it to MP3 at a bitrate and sample rate you choose. Perfect for fitting audio into email attachments, messaging apps, or storage limits.</p>
-            <h3>How It Works</h3>
-            <p>Lossy MP3 compression removes inaudible data to shrink the file. A 44 MB WAV can become a 4 MB MP3 at 128 kbps — roughly a 10x reduction with minimal quality loss for most uses. Higher bitrates (256–320 kbps) preserve more detail for music. Everything runs in your browser, with the LAME MP3 encoder compiled to WebAssembly — nothing is uploaded.</p>
-            <h3>Choosing the Right Bitrate</h3>
-            <p>64 kbps — voice recordings and podcasts (smallest files). 128 kbps — general purpose, good quality for most uses. 192 kbps — high quality for music. 320 kbps — maximum quality, indistinguishable from uncompressed for most listeners. Lowering the sample rate to 22 kHz or 16 kHz shrinks speech files further.</p>
-            <p>Need other edits? Try our <a href="/converter/">Audio Converter</a>, <a href="/audio-trimmer/">Audio Trimmer</a>, <a href="/audio-joiner/">Audio Joiner</a>, or <a href="/volume-booster/">Volume Booster</a>.</p>
+            <h2>Compress MP3 and other audio files online</h2>
+            <p>Audio Compressor makes audio files smaller by re-encoding them to MP3 at the bitrate and sample rate you choose. It shows the expected size before you start, handles one file or a whole batch, and runs in your browser with the LAME MP3 encoder compiled to WebAssembly, so nothing is uploaded.</p>
+            <h3>How to compress an audio file</h3>
+            <ol>
+                <li>Drop one or several files on the box above (MP3, WAV, M4A, FLAC, OGG).</li>
+                <li>Choose a bitrate; for speech, a lower sample rate makes the file smaller still.</li>
+                <li>Check the estimated size.</li>
+                <li>Click “Compress &amp; Download”. With several files, download each one or all of them as a ZIP.</li>
+            </ol>
+            <h3>How small will the file be?</h3>
+            <p>An MP3's size depends only on its bitrate and length: about 1 MB per minute at 128 kbps and about 0.5 MB per minute at 64 kbps. A 10-minute recording is roughly 10 MB at 128 kbps and 5 MB at 64 kbps.</p>
+            <h3>Which bitrate to choose</h3>
+            <ul>
+                <li>64 kbps — voice recordings, lectures and podcasts (smallest files)</li>
+                <li>128 kbps — general purpose, good for most uses</li>
+                <li>192 kbps — music in high quality</li>
+                <li>320 kbps — maximum quality, for when size matters least</li>
+            </ul>
+            <h3>Fit email and chat limits</h3>
+            <p>Most email services cap attachments at 20–25 MB: roughly 20–25 minutes of audio at 128 kbps, or 40–50 minutes at 64 kbps. For voice, 64 kbps at 22050 Hz keeps speech clear at the smallest size.</p>
+            <h3>WAV to MP3: the biggest saving</h3>
+            <p>Uncompressed WAV (CD quality) takes about 10.6 MB per minute. Compressing it to MP3 at 128 kbps makes it about 11 times smaller with little audible difference for most uses.</p>
+            <p>Need other edits? Join files first with the <a href="/audio-joiner/">audio joiner</a>, cut silence at the ends with the <a href="/audio-trimmer/">audio trimmer</a>, make a quiet recording louder with the <a href="/volume-booster/">volume booster</a>, or save M4A or FLAC with the <a href="/converter/">audio converter</a>.</p>
         </section>
 
         <section class="faq">
             <h2>Frequently Asked Questions</h2>
-            <div class="faq-item"><div class="faq-q">How much can I reduce file size?</div><div class="faq-a">Depending on the source, you can reduce WAV files by 5–20x by converting to MP3. A 50 MB WAV becomes ~5 MB at 128 kbps.</div></div>
-            <div class="faq-item"><div class="faq-q">Does compression affect quality?</div><div class="faq-a">Lossy compression removes some data. At 192 kbps or higher, most listeners cannot tell the difference from the original.</div></div>
+            <div class="faq-item"><div class="faq-q">How do I reduce the size of an MP3 file?</div><div class="faq-a">Re-encode it at a lower bitrate. Drop the MP3 here, pick 128 kbps or 64 kbps, and download the smaller file. Lowering the sample rate to 22050 Hz shrinks voice recordings further.</div></div>
+            <div class="faq-item"><div class="faq-q">How much smaller will my file be?</div><div class="faq-a">About 1 MB per minute at 128 kbps and 0.5 MB per minute at 64 kbps. A WAV file usually becomes 5 to 20 times smaller. The tool shows the estimate before you compress.</div></div>
+            <div class="faq-item"><div class="faq-q">Does compression affect quality?</div><div class="faq-a">Lossy compression removes some data. At 192 kbps or higher, most listeners cannot tell the difference from the original; for speech, 64 kbps is enough.</div></div>
             <div class="faq-item"><div class="faq-q">Can I compress several files at once?</div><div class="faq-a">Yes. Drop several files: all of them are compressed with the same settings, and you can download each one or all of them as a ZIP.</div></div>
-            <div class="faq-item"><div class="faq-q">Is my audio uploaded?</div><div class="faq-a">No. All compression happens in your browser using the Web Audio API.</div></div>
+            <div class="faq-item"><div class="faq-q">Which sample rate should I use for voice?</div><div class="faq-a">22050 Hz keeps speech clear and makes the file smaller. 16000 Hz is the smallest and still fine for speech, but not for music.</div></div>
+            <div class="faq-item"><div class="faq-q">Is my audio uploaded?</div><div class="faq-a">No. All compression happens in your browser.</div></div>
         </section>
     </div>
     <footer class="at-footer">
diff --git a/audio-joiner/index.html b/audio-joiner/index.html
index aa16135..af68436 100644
--- a/audio-joiner/index.html
+++ b/audio-joiner/index.html
@@ -13,9 +13,9 @@
       gtag('js', new Date());
       gtag('config', 'G-62ZJNZFRES');
     </script>
-    <title>Audio Joiner — Merge MP3, WAV Files Free | AudioTools.dev</title>
-    <meta name="description" content="Free online audio joiner. Merge and combine MP3, WAV, FLAC files in your browser. No upload, no sign-up. Add crossfade between tracks.">
-    <meta name="keywords" content="audio joiner, merge audio online, combine mp3, join audio files, audio merger, concatenate audio, merge wav files free">
+    <title>Audio Joiner — Merge MP3 Files Online, Free | AudioTools.dev</title>
+    <meta name="description" content="Merge MP3, WAV, M4A and voice messages into one file in your browser. Reorder tracks, add a crossfade, save as MP3 or WAV. Free, no upload, no sign-up.">
+    <meta name="keywords" content="merge mp3 files, audio joiner, combine audio files, join mp3 online, merge audio online, merge voice messages, mp3 merger, combine mp3 free">
     <link rel="canonical" href="https://audiotools.dev/audio-joiner/">
     <link rel="alternate" hreflang="en" href="https://audiotools.dev/audio-joiner/">
     <link rel="alternate" hreflang="zh" href="https://audiotools.dev/zh/audio-joiner/">
@@ -24,22 +24,22 @@
     <meta property="og:site_name" content="AudioTools.dev">
     <meta property="og:locale" content="en_US">
     <meta property="og:url" content="https://audiotools.dev/audio-joiner/">
-    <meta property="og:title" content="Audio Joiner — Merge MP3, WAV Files Free | AudioTools">
-    <meta property="og:description" content="Free online audio joiner. Merge and combine MP3, WAV, FLAC files in your browser. No upload, add crossfade between tracks.">
+    <meta property="og:title" content="Audio Joiner — Merge MP3 Files Online, Free">
+    <meta property="og:description" content="Merge MP3, WAV, M4A and voice messages into one file in your browser. Reorder tracks, add a crossfade, save as MP3 or WAV. Free, no upload, no sign-up.">
     <meta property="og:image" content="https://audiotools.dev/og/audio-joiner.png">
     <meta property="og:image:width" content="1200">
     <meta property="og:image:height" content="630">
-    <meta property="og:image:alt" content="Audio Joiner — Merge MP3, WAV Files Free | AudioTools">
+    <meta property="og:image:alt" content="Audio Joiner — Merge MP3 Files Online, Free">
     <meta name="twitter:card" content="summary_large_image">
-    <meta name="twitter:title" content="Audio Joiner — Merge MP3, WAV Files Free | AudioTools">
-    <meta name="twitter:description" content="Free online audio joiner. Merge and combine MP3, WAV, FLAC files in your browser. No upload, add crossfade between tracks.">
+    <meta name="twitter:title" content="Audio Joiner — Merge MP3 Files Online, Free">
+    <meta name="twitter:description" content="Merge MP3, WAV, M4A and voice messages into one file in your browser. Reorder tracks, add a crossfade, save as MP3 or WAV. Free, no upload, no sign-up.">
     <meta name="twitter:image" content="https://audiotools.dev/og/audio-joiner.png">
     <meta name="robots" content="index, follow, max-snippet:-1, max-image-preview:large">
     <link rel="icon" type="image/svg+xml" href="/favicon.svg">
     <link rel="icon" type="image/x-icon" href="/favicon.ico">
     <link rel="apple-touch-icon" href="/apple-touch-icon.png">
     <script type="application/ld+json">
-    {"@context":"https://schema.org","@type":"WebApplication","name":"Audio Joiner — AudioTools.dev","url":"https://audiotools.dev/audio-joiner/","description":"Free online audio joiner. Merge and combine MP3, WAV, FLAC files in your browser. No upload, no sign-up. Add crossfade between tracks.","applicationCategory":"MultimediaApplication","operatingSystem":"Any","isAccessibleForFree":true,"offers":{"@type":"Offer","price":"0","priceCurrency":"USD"}}
+    {"@context":"https://schema.org","@type":"WebApplication","name":"Audio Joiner — AudioTools.dev","url":"https://audiotools.dev/audio-joiner/","description":"Merge MP3, WAV, M4A and voice messages into one file in your browser. Reorder tracks, add a crossfade, save as MP3 or WAV. Free, no upload, no sign-up.","applicationCategory":"MultimediaApplication","operatingSystem":"Any","isAccessibleForFree":true,"offers":{"@type":"Offer","price":"0","priceCurrency":"USD"}}
     </script>
     <script type="application/ld+json">
     {
@@ -48,10 +48,10 @@
         "mainEntity": [
             {
                 "@type": "Question",
-                "name": "How do I merge audio files online?",
+                "name": "How do I merge MP3 files into one?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "Add your files, arrange them in order, optionally add crossfade, then click Merge & Download to get a single combined file."
+                    "text": "Add the MP3 files, arrange them in order, optionally set a crossfade, then click Merge & Download. You get one MP3 or WAV file, made in your browser."
                 }
             },
             {
@@ -59,7 +59,31 @@
                 "name": "Can I merge different formats?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "Yes. Mix MP3, WAV, FLAC, OGG. The browser decodes each file and the merged result is saved as MP3 or WAV."
+                    "text": "Yes. MP3, WAV, M4A, FLAC, OGG and Opus can be mixed in one merge. Each file is decoded by your browser and the result is saved as MP3 or WAV."
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "Can I combine WhatsApp or Telegram voice messages?",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "Yes. Save the voice messages from the chat (they are.opus or.ogg files) and add them here. Chrome, Edge and Firefox play these files; some older Safari versions do not."
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "Does merging reduce audio quality?",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "Saving as WAV keeps the decoded audio unchanged. Saving as MP3 re-encodes it at 192 kbps, which sounds the same as the original for speech and most music."
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "Is there a limit on the number of files?",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "No fixed limit. The only limit is your device's memory, since all tracks are held in it while merging."
                 }
             },
             {
@@ -148,8 +172,8 @@
     <div class="container">
         <section class="hero">
             <svg class="hero-glyph" viewBox="0 0 160 56" aria-hidden="true"><polyline class="g-ink" points="4,28 10,18 16,38 22,14 28,42 34,20 40,36 46,24 52,30 58,28"/><polyline class="g-ink" points="102,28 108,22 114,34 120,12 126,44 132,18 138,38 144,16 150,40 156,28"/><path class="g-acc" d="M58 28 C72 28 72 14 80 14 S88 28 102 28 M58 28 C72 28 72 42 80 42 S88 28 102 28"/></svg>
-            <h1>Audio Joiner</h1>
-            <p>Merge and combine multiple audio files into one — reorder tracks, add crossfade, no upload</p>
+            <h1>Merge Audio Files</h1>
+            <p>Join MP3s, voice messages and other audio into one track — reorder, crossfade, no upload</p>
         </section>
 
         <div class="tool-area">
@@ -198,21 +222,39 @@ <h1>Audio Joiner</h1>
         </div>
 
         <section class="seo-content">
-            <h2>Free Online Audio Joiner &amp; Merger</h2>
-            <p>Audio Joiner combines multiple audio files into a single track directly in your browser. Whether you need to merge podcast segments, combine music tracks, or join voice recordings, this tool handles it without uploading your files to any server.</p>
-            <h3>How It Works</h3>
-            <p>The tool uses the Web Audio API to decode each file into raw PCM, concatenates the buffers in the order you set, applies an optional crossfade between consecutive tracks, and encodes the result as MP3 or WAV. All processing happens in your browser — no server involved.</p>
-            <h3>Reorder and Crossfade</h3>
-            <p>Drag tracks to reorder them, or use the up/down arrows. Set a crossfade of up to 3 seconds to smoothly blend the end of one track into the start of the next — useful for music mixes and seamless podcast edits. Set crossfade to 0 for a clean back-to-back join.</p>
-            <h3>Common Use Cases</h3>
-            <p>Merging podcast intro, segments, and outro. Combining multiple music tracks into one mix. Joining split voice recordings or audiobook chapters. Assembling sound effects into a single file.</p>
-            <p>Need other edits? Try our <a href="/audio-trimmer/">Audio Trimmer</a>, <a href="/audio-speed-changer/">Speed Changer</a>, <a href="/volume-booster/">Volume Booster</a>, or <a href="/converter/">Audio Converter</a>.</p>
+            <h2>Merge MP3 and other audio files online</h2>
+            <p>Add your files, put them in order and download one file. Audio Joiner runs entirely in your browser: the files are decoded, joined and encoded on your device, so nothing is uploaded, and there is no size quota and no waiting in line.</p>
+            <h3>How to merge audio files</h3>
+            <ol>
+                <li>Drop your files on the box above, or click to choose them. You can add more later with “Add more files”.</li>
+                <li>Drag the tracks into the order you want, or use the arrows.</li>
+                <li>Optionally set a crossfade of up to 3 seconds for a smooth transition. Leave it at 0 for a straight cut.</li>
+                <li>Click “Merge &amp; Download” and save the result as MP3 (192 kbps) or WAV.</li>
+            </ol>
+            <h3>What you can merge</h3>
+            <p>MP3, WAV, M4A/AAC, FLAC, OGG and Opus files, mixed in any order: anything your browser can play. Voice messages saved from WhatsApp or Telegram (.opus, .ogg) work in browsers that play Opus, such as Chrome, Edge and Firefox. Mono and stereo files can be mixed, and files with different sample rates are brought to one rate automatically.</p>
+            <h3>Common uses</h3>
+            <ul>
+                <li>A podcast episode with its intro and outro</li>
+                <li>Several voice messages as one recording</li>
+                <li>Audiobook chapters as a single file</li>
+                <li>Songs into a mix, with a crossfade between them</li>
+                <li>Sound effects or ringtone parts in sequence</li>
+            </ul>
+            <h3>On iPhone and Android</h3>
+            <p>There is nothing to install: open this page in Safari on an iPhone or Chrome on Android, add the files from your phone and download the merged file.</p>
+            <h3>Limits</h3>
+            <p>The joiner keeps all tracks in your device's memory while it works. An hour or two of audio is fine on most computers; on a phone, very long merges can run out of memory, so join them in a few parts.</p>
+            <p>To make the merged file smaller, use the <a href="/audio-compressor/">audio compressor</a>; to cut a part out first, the <a href="/audio-trimmer/">audio trimmer</a>; for M4A or FLAC, the <a href="/converter/">audio converter</a>; and if one recording is quieter than the rest, the <a href="/volume-booster/">volume booster</a>.</p>
         </section>
 
         <section class="faq">
             <h2>Frequently Asked Questions</h2>
-            <div class="faq-item"><div class="faq-q">How do I merge audio files online?</div><div class="faq-a">Add your files, arrange them in order, optionally add crossfade, then click Merge &amp; Download to get a single combined file.</div></div>
-            <div class="faq-item"><div class="faq-q">Can I merge different formats?</div><div class="faq-a">Yes. Mix MP3, WAV, FLAC, OGG. The browser decodes each file and the merged result is saved as MP3 or WAV.</div></div>
+            <div class="faq-item"><div class="faq-q">How do I merge MP3 files into one?</div><div class="faq-a">Add the MP3 files, arrange them in order, optionally set a crossfade, then click Merge &amp; Download. You get one MP3 or WAV file, made in your browser.</div></div>
+            <div class="faq-item"><div class="faq-q">Can I merge different formats?</div><div class="faq-a">Yes. MP3, WAV, M4A, FLAC, OGG and Opus can be mixed in one merge. Each file is decoded by your browser and the result is saved as MP3 or WAV.</div></div>
+            <div class="faq-item"><div class="faq-q">Can I combine WhatsApp or Telegram voice messages?</div><div class="faq-a">Yes. Save the voice messages from the chat (they are .opus or .ogg files) and add them here. Chrome, Edge and Firefox play these files; some older Safari versions do not.</div></div>
+            <div class="faq-item"><div class="faq-q">Does merging reduce audio quality?</div><div class="faq-a">Saving as WAV keeps the decoded audio unchanged. Saving as MP3 re-encodes it at 192 kbps, which sounds the same as the original for speech and most music.</div></div>
+            <div class="faq-item"><div class="faq-q">Is there a limit on the number of files?</div><div class="faq-a">No fixed limit. The only limit is your device's memory, since all tracks are held in it while merging.</div></div>
             <div class="faq-item"><div class="faq-q">Is my audio uploaded?</div><div class="faq-a">No. All merging happens in your browser using the Web Audio API.</div></div>
         </section>
     </div>
diff --git a/scripts/build_zh.py b/scripts/build_zh.py
index aa21736..5a09dc1 100644
--- a/scripts/build_zh.py
+++ b/scripts/build_zh.py
@@ -97,7 +97,7 @@ def build(tool, table):
 
 
 ALLOWED = {'AudioTools.dev', 'AudioTools', 'GitHub', 'DevToolKit.site', 'Boosty', 'Roman Gordienko', 'MP3', 'WAV', 'FLAC', 'OGG',
-           'M4A', 'AAC', 'WebM', 'ZIP', 'Web Audio API', 'Web Speech Synthesis API', 'Speech Synthesis API', 'dBFS', 'kbps', 'TTS', 'EN', 'Google', 'Chrome', 'Safari', 'Edge', 'Windows', 'macOS', 'Android', 'LAME', 'WebAssembly', 'PCM'}
+           'M4A', 'AAC', 'WebM', 'ZIP', 'Web Audio API', 'Web Speech Synthesis API', 'Speech Synthesis API', 'dBFS', 'kbps', 'TTS', 'EN', 'Google', 'Chrome', 'Safari', 'Edge', 'Windows', 'macOS', 'Android', 'LAME', 'WebAssembly', 'PCM', 'Firefox', 'Opus', 'opus', 'Telegram', 'WhatsApp', 'iPhone'}
 
 
 def leftovers(path, s):
@@ -195,92 +195,162 @@ def update_hand_made(path, current, en_href):
      '<div class="faq-q">我的音频会被上传吗？</div><div class="faq-a">不会。所有处理都通过 Web Audio API 在您的浏览器中完成。</div>'),
 ],
 'audio-joiner': [
-    ('<title>Audio Joiner — Merge MP3, WAV Files Free | AudioTools.dev</title>', '<title>音频合并 — 免费在线合并 MP3、WAV 文件 | AudioTools.dev</title>'),
-    ('Free online audio joiner. Merge and combine MP3, WAV, FLAC files in your browser. No upload, no sign-up. Add crossfade between tracks.',
-     '免费在线音频合并工具：在浏览器中合并、拼接 MP3、WAV、FLAC 文件。无需上传，无需注册，可在音轨之间添加淡入淡出。'),
-    ('Free online audio joiner. Merge and combine MP3, WAV, FLAC files in your browser. No upload, add crossfade between tracks.',
-     '免费在线音频合并工具：在浏览器中合并 MP3、WAV、FLAC 文件。无需上传，可添加淡入淡出。'),
-    ('audio joiner, merge audio online, combine mp3, join audio files, audio merger, concatenate audio, merge wav files free',
-     '音频合并, 在线合并音频, MP3合并, 拼接音频文件, 音频拼接, 合并WAV, 免费音频合并'),
-    ('Audio Joiner — Merge MP3, WAV Files Free | AudioTools', '音频合并 — 免费在线合并 MP3、WAV 文件 | AudioTools'),
-    ('"name":"Audio Joiner — AudioTools.dev"', '"name":"音频合并 — AudioTools.dev"'),
-    ('<h1>Audio Joiner</h1>', '<h1>音频合并</h1>'),
-    ('<p>Merge and combine multiple audio files into one — reorder tracks, add crossfade, no upload</p>', '<p>把多个音频文件合并为一个——可调整顺序、添加淡入淡出，无需上传</p>'),
-    ('<p><strong>Drop audio files here</strong> or click to browse</p>', '<p><strong>将音频文件拖放到此处</strong>，或点击选择</p>'),
-    ('<p>Add several files — MP3, WAV, FLAC, OGG, M4A. Processed locally, never uploaded.</p>', '<p>可添加多个文件——MP3、WAV、FLAC、OGG、M4A。在本地处理，绝不上传。</p>'),
-    ('>＋ Add more files</button>', '>＋ 添加更多文件</button>'),
-    ('<label>Crossfade:</label>', '<label>淡入淡出：</label>'),
-    ('<div class="total-line">Tracks: <b id="trackCount">0</b> · Total length: <b id="totalDur">0:00</b></div>', '<div class="total-line">音轨：<b id="trackCount">0</b> · 总时长：<b id="totalDur">0:00</b></div>'),
-    ('>Merge &amp; Download</button>', '>合并并下载</button>'),
-    ('>Clear</button>', '>清空</button>'),
-    ('<div class="progress-text" id="progressText">Merging…</div>', '<div class="progress-text" id="progressText">合并中…</div>'),
-    ("progressText.textContent='Merging…';", "progressText.textContent='合并中…';"),
-    ("progressText.textContent='Encoding…';", "progressText.textContent='编码中…';"),
-    ('<p class="result-title">Merged — <span', '<p class="result-title">合并完成 — <span'),
-    ('id="downloadBtn" style="width:100%;">Download</button>', 'id="downloadBtn" style="width:100%;">下载</button>'),
-    ("alert('Could not decode \"' + file.name + '\". Skipping. Try MP3, WAV, FLAC, OGG or M4A.');", "alert('无法解码“' + file.name + '”，已跳过。请使用 MP3、WAV、FLAC、OGG 或 M4A。');"),
-    ('title="Move up"', 'title="上移"'),
-    ('title="Move down"', 'title="下移"'),
-    ("resultInfo.textContent = tracks.length + ' tracks · '", "resultInfo.textContent = tracks.length + ' 条音轨 · '"),
+    ('"name":"Audio Joiner — AudioTools.dev"',
+     '"name":"音频合并 — AudioTools.dev"'),
+    ('<p><strong>Drop audio files here</strong> or click to browse</p>',
+     '<p><strong>将音频文件拖放到此处</strong>，或点击选择</p>'),
+    ('<p>Add several files — MP3, WAV, FLAC, OGG, M4A. Processed locally, never uploaded.</p>',
+     '<p>可添加多个文件——MP3、WAV、FLAC、OGG、M4A。在本地处理，绝不上传。</p>'),
+    ('>＋ Add more files</button>',
+     '>＋ 添加更多文件</button>'),
+    ('<label>Crossfade:</label>',
+     '<label>淡入淡出：</label>'),
+    ('<div class="total-line">Tracks: <b id="trackCount">0</b> · Total length: <b id="totalDur">0:00</b></div>',
+     '<div class="total-line">音轨：<b id="trackCount">0</b> · 总时长：<b id="totalDur">0:00</b></div>'),
+    ('>Merge &amp; Download</button>',
+     '>合并并下载</button>'),
+    ('>Clear</button>',
+     '>清空</button>'),
+    ('<div class="progress-text" id="progressText">Merging…</div>',
+     '<div class="progress-text" id="progressText">合并中…</div>'),
+    ("progressText.textContent='Merging…';",
+     "progressText.textContent='合并中…';"),
+    ("progressText.textContent='Encoding…';",
+     "progressText.textContent='编码中…';"),
+    ('<p class="result-title">Merged — <span',
+     '<p class="result-title">合并完成 — <span'),
+    ('id="downloadBtn" style="width:100%;">Download</button>',
+     'id="downloadBtn" style="width:100%;">下载</button>'),
+    ('alert(\'Could not decode "\' + file.name + \'". Skipping. Try MP3, WAV, FLAC, OGG or M4A.\');',
+     "alert('无法解码“' + file.name + '”，已跳过。请使用 MP3、WAV、FLAC、OGG 或 M4A。');"),
+    ('title="Move up"',
+     'title="上移"'),
+    ('title="Move down"',
+     'title="下移"'),
+    ("resultInfo.textContent = tracks.length + ' tracks · '",
+     "resultInfo.textContent = tracks.length + ' 条音轨 · '"),
     ('<div class="feature-title">Multiple Files</div><div class="feature-desc">Add any number of audio files and reorder them freely.</div>',
      '<div class="feature-title">多个文件</div><div class="feature-desc">可添加任意数量的音频文件，并自由调整顺序。</div>'),
     ('<div class="feature-title">Crossfade Transitions</div><div class="feature-desc">Add a smooth crossfade between tracks for seamless joins.</div>',
      '<div class="feature-title">淡入淡出过渡</div><div class="feature-desc">在音轨之间添加平滑的淡入淡出，衔接自然。</div>'),
     ('<div class="feature-title">Mix Formats</div><div class="feature-desc">Combine MP3, WAV, FLAC, OGG in any combination.</div>',
      '<div class="feature-title">混合格式</div><div class="feature-desc">MP3、WAV、FLAC、OGG 可任意组合。</div>'),
-    ('<div class="feature-desc">All merging in your browser. Files never leave your device.</div>', '<div class="feature-desc">所有合并都在浏览器中完成，文件不会离开您的设备。</div>'),
-    ('<h2>Free Online Audio Joiner &amp; Merger</h2>', '<h2>免费在线音频合并与拼接</h2>'),
-    ('<p>Audio Joiner combines multiple audio files into a single track directly in your browser. Whether you need to merge podcast segments, combine music tracks, or join voice recordings, this tool handles it without uploading your files to any server.</p>',
-     '<p>音频合并工具直接在浏览器中把多个音频文件合成一条音轨。无论是合并播客片段、拼接音乐，还是连接语音录音，都不需要把文件上传到任何服务器。</p>'),
-    ('<p>The tool uses the Web Audio API to decode each file into raw PCM, concatenates the buffers in the order you set, applies an optional crossfade between consecutive tracks, and encodes the result as MP3 or WAV. All processing happens in your browser — no server involved.</p>',
-     '<p>工具使用 Web Audio API 把每个文件解码为原始 PCM，按您设定的顺序拼接，可选在相邻音轨之间添加淡入淡出，再编码为 MP3 或 WAV。所有处理都在浏览器中完成，不涉及服务器。</p>'),
-    ('<h3>Reorder and Crossfade</h3>', '<h3>调整顺序与淡入淡出</h3>'),
-    ('<p>Drag tracks to reorder them, or use the up/down arrows. Set a crossfade of up to 3 seconds to smoothly blend the end of one track into the start of the next — useful for music mixes and seamless podcast edits. Set crossfade to 0 for a clean back-to-back join.</p>',
-     '<p>拖动音轨即可调整顺序，也可以使用上下箭头。淡入淡出最长可设为 3 秒，让上一条音轨的结尾平滑过渡到下一条的开头，适合音乐串烧和无缝的播客剪辑。设为 0 则直接首尾相接。</p>'),
-    ('<p>Merging podcast intro, segments, and outro. Combining multiple music tracks into one mix. Joining split voice recordings or audiobook chapters. Assembling sound effects into a single file.</p>',
-     '<p>合并播客的片头、正片和片尾；把多首音乐拼成一个串烧；连接分段的语音录音或有声书章节；把多个音效合成一个文件。</p>'),
-    ('<p>Need other edits? Try our <a href="/audio-trimmer/">Audio Trimmer</a>, <a href="/audio-speed-changer/">Speed Changer</a>, <a href="/volume-booster/">Volume Booster</a>, or <a href="/converter/">Audio Converter</a>.</p>',
-     '<p>还需要其他处理？试试<a href="/audio-trimmer/">音频剪辑</a>、<a href="/audio-speed-changer/">音频变速</a>、<a href="/volume-booster/">音量增强器</a>或<a href="/converter/">音频转换器</a>。</p>'),
-    ('<div class="faq-q">How do I merge audio files online?</div><div class="faq-a">Add your files, arrange them in order, optionally add crossfade, then click Merge &amp; Download to get a single combined file.</div>',
-     '<div class="faq-q">如何在线合并音频文件？</div><div class="faq-a">添加文件，排好顺序，可选添加淡入淡出，然后点击“合并并下载”，即可得到一个合并后的文件。</div>'),
-    ('<div class="faq-q">Can I merge different formats?</div><div class="faq-a">Yes. Mix MP3, WAV, FLAC, OGG. The browser decodes each file and the merged result is saved as MP3 or WAV.</div>',
-     '<div class="faq-q">可以合并不同格式的文件吗？</div><div class="faq-a">可以。MP3、WAV、FLAC、OGG 可混合使用。浏览器会分别解码每个文件，合并结果保存为 MP3 或 WAV。</div>'),
+    ('<div class="feature-desc">All merging in your browser. Files never leave your device.</div>',
+     '<div class="feature-desc">所有合并都在浏览器中完成，文件不会离开您的设备。</div>'),
     ('<div class="faq-q">Is my audio uploaded?</div><div class="faq-a">No. All merging happens in your browser using the Web Audio API.</div>',
      '<div class="faq-q">我的音频会被上传吗？</div><div class="faq-a">不会。所有合并都通过 Web Audio API 在您的浏览器中完成。</div>'),
+    ('<title>Audio Joiner — Merge MP3 Files Online, Free | AudioTools.dev</title>',
+     '<title>音频合并 — 免费在线合并 MP3 文件 | AudioTools.dev</title>'),
+    ('Merge MP3, WAV, M4A and voice messages into one file in your browser. Reorder tracks, add a crossfade, save as MP3 or WAV. Free, no upload, no sign-up.',
+     '在浏览器中把 MP3、WAV、M4A 和语音消息合并为一个文件。可调整顺序、添加淡入淡出，保存为 MP3 或 WAV。免费，无需上传，无需注册。'),
+    ('Audio Joiner — Merge MP3 Files Online, Free',
+     '音频合并 — 免费在线合并 MP3 文件'),
+    ('merge mp3 files, audio joiner, combine audio files, join mp3 online, merge audio online, merge voice messages, mp3 merger, combine mp3 free',
+     'MP3合并, 音频合并, 合并音频文件, 在线合并MP3, 拼接音频, 合并语音消息, 音频拼接工具, 免费合并MP3'),
+    ('<h1>Merge Audio Files</h1>',
+     '<h1>音频合并</h1>'),
+    ('<p>Join MP3s, voice messages and other audio into one track — reorder, crossfade, no upload</p>',
+     '<p>把 MP3、语音消息等音频合并成一条音轨——可调整顺序、淡入淡出，无需上传</p>'),
+    ('<h2>Merge MP3 and other audio files online</h2>',
+     '<h2>在线合并 MP3 等音频文件</h2>'),
+    ('<p>Add your files, put them in order and download one file. Audio Joiner runs entirely in your browser: the files are decoded, joined and encoded on your device, so nothing is uploaded, and there is no size quota and no waiting in line.</p>',
+     '<p>添加文件、排好顺序，下载一个文件即可。音频合并完全在浏览器中运行：文件在您的设备上解码、拼接和编码，因此不上传任何内容，没有大小配额，也不用排队等待。</p>'),
+    ('<h3>How to merge audio files</h3>',
+     '<h3>如何合并音频文件</h3>'),
+    ('<li>Drop your files on the box above, or click to choose them. You can add more later with “Add more files”.</li>',
+     '<li>把文件拖放到上方的框中，或点击选择。之后还可以用“添加更多文件”继续添加。</li>'),
+    ('<li>Drag the tracks into the order you want, or use the arrows.</li>',
+     '<li>拖动音轨排出想要的顺序，或使用箭头调整。</li>'),
+    ('<li>Optionally set a crossfade of up to 3 seconds for a smooth transition. Leave it at 0 for a straight cut.</li>',
+     '<li>可选：设置最长 3 秒的淡入淡出，让过渡更平滑。保持 0 则直接衔接。</li>'),
+    ('<li>Click “Merge &amp; Download” and save the result as MP3 (192 kbps) or WAV.</li>',
+     '<li>点击“合并并下载”，将结果保存为 MP3（192 kbps）或 WAV。</li>'),
+    ('<h3>What you can merge</h3>',
+     '<h3>可以合并哪些文件</h3>'),
+    ('<p>MP3, WAV, M4A/AAC, FLAC, OGG and Opus files, mixed in any order: anything your browser can play. Voice messages saved from WhatsApp or Telegram (.opus, .ogg) work in browsers that play Opus, such as Chrome, Edge and Firefox. Mono and stereo files can be mixed, and files with different sample rates are brought to one rate automatically.</p>',
+     '<p>MP3、WAV、M4A/AAC、FLAC、OGG 和 Opus 文件可按任意顺序混合，只要浏览器能播放即可。从 WhatsApp 或 Telegram 保存的语音消息（.opus、.ogg）在支持 Opus 的浏览器中可用，例如 Chrome、Edge 和 Firefox。单声道和立体声可以混合，不同采样率的文件会自动统一。</p>'),
+    ('<h3>Common uses</h3>',
+     '<h3>常见用途</h3>'),
+    ('<li>A podcast episode with its intro and outro</li>',
+     '<li>给一期播客接上片头和片尾</li>'),
+    ('<li>Several voice messages as one recording</li>',
+     '<li>把几条语音消息合成一段录音</li>'),
+    ('<li>Audiobook chapters as a single file</li>',
+     '<li>把有声书的各章合成一个文件</li>'),
+    ('<li>Songs into a mix, with a crossfade between them</li>',
+     '<li>把多首歌曲做成串烧，中间加淡入淡出</li>'),
+    ('<li>Sound effects or ringtone parts in sequence</li>',
+     '<li>按顺序拼接音效或铃声片段</li>'),
+    ('<h3>On iPhone and Android</h3>',
+     '<h3>在 iPhone 和 Android 上使用</h3>'),
+    ('<p>There is nothing to install: open this page in Safari on an iPhone or Chrome on Android, add the files from your phone and download the merged file.</p>',
+     '<p>无需安装任何应用：在 iPhone 的 Safari 或 Android 的 Chrome 中打开本页，从手机添加文件，下载合并后的文件即可。</p>'),
+    ('<h3>Limits</h3>',
+     '<h3>限制</h3>'),
+    ("<p>The joiner keeps all tracks in your device's memory while it works. An hour or two of audio is fine on most computers; on a phone, very long merges can run out of memory, so join them in a few parts.</p>",
+     '<p>合并过程中，所有音轨都保存在设备内存里。大多数电脑处理一两个小时的音频没有问题；在手机上，过长的合并可能内存不足，可以分几次合并。</p>'),
+    ('<p>To make the merged file smaller, use the <a href="/audio-compressor/">audio compressor</a>; to cut a part out first, the <a href="/audio-trimmer/">audio trimmer</a>; for M4A or FLAC, the <a href="/converter/">audio converter</a>; and if one recording is quieter than the rest, the <a href="/volume-booster/">volume booster</a>.</p>',
+     '<p>想让合并后的文件更小，用<a href="/audio-compressor/">音频压缩</a>；想先剪掉一部分，用<a href="/audio-trimmer/">音频剪辑</a>；需要 M4A 或 FLAC，用<a href="/converter/">音频转换器</a>；某段录音比其他的小声，用<a href="/volume-booster/">音量增强器</a>。</p>'),
+    ('<div class="faq-q">How do I merge MP3 files into one?</div><div class="faq-a">Add the MP3 files, arrange them in order, optionally set a crossfade, then click Merge &amp; Download. You get one MP3 or WAV file, made in your browser.</div>',
+     '<div class="faq-q">如何把多个 MP3 合并成一个？</div><div class="faq-a">添加 MP3 文件，排好顺序，可选设置淡入淡出，然后点击“合并并下载”。您会得到一个在浏览器中生成的 MP3 或 WAV 文件。</div>'),
+    ('<div class="faq-q">Can I merge different formats?</div><div class="faq-a">Yes. MP3, WAV, M4A, FLAC, OGG and Opus can be mixed in one merge. Each file is decoded by your browser and the result is saved as MP3 or WAV.</div>',
+     '<div class="faq-q">可以合并不同格式的文件吗？</div><div class="faq-a">可以。MP3、WAV、M4A、FLAC、OGG 和 Opus 可以在一次合并中混用。每个文件由浏览器解码，结果保存为 MP3 或 WAV。</div>'),
+    ('<div class="faq-q">Can I combine WhatsApp or Telegram voice messages?</div><div class="faq-a">Yes. Save the voice messages from the chat (they are .opus or .ogg files) and add them here. Chrome, Edge and Firefox play these files; some older Safari versions do not.</div>',
+     '<div class="faq-q">可以合并 WhatsApp 或 Telegram 的语音消息吗？</div><div class="faq-a">可以。从聊天中保存语音消息（.opus 或 .ogg 文件），然后添加到这里。Chrome、Edge 和 Firefox 可以播放这类文件，部分旧版 Safari 不行。</div>'),
+    ('<div class="faq-q">Does merging reduce audio quality?</div><div class="faq-a">Saving as WAV keeps the decoded audio unchanged. Saving as MP3 re-encodes it at 192 kbps, which sounds the same as the original for speech and most music.</div>',
+     '<div class="faq-q">合并会降低音质吗？</div><div class="faq-a">保存为 WAV 时，解码后的音频保持不变。保存为 MP3 时会以 192 kbps 重新编码，对语音和大多数音乐来说听起来与原文件相同。</div>'),
+    ('<div class="faq-q">Is there a limit on the number of files?</div><div class="faq-a">No fixed limit. The only limit is your device\'s memory, since all tracks are held in it while merging.</div>',
+     '<div class="faq-q">文件数量有限制吗？</div><div class="faq-a">没有固定限制。唯一的限制是设备内存，因为合并时所有音轨都保存在内存中。</div>'),
 ],
 'audio-compressor': [
-    ('<title>Audio Compressor — Reduce File Size Free | AudioTools.dev</title>', '<title>音频压缩 — 免费在线减小音频文件大小 | AudioTools.dev</title>'),
-    ('Compress audio files online for free. Reduce MP3, WAV file size by adjusting bitrate and sample rate. No upload, runs in your browser.',
-     '免费在线压缩音频：调整码率和采样率，减小 MP3、WAV 文件体积。无需上传，在浏览器中运行。'),
-    ('audio compressor, reduce audio file size, compress mp3 online, shrink audio file, audio bitrate reducer, compress wav free',
-     '音频压缩, 减小音频文件大小, 在线压缩MP3, 音频变小, 降低码率, 压缩WAV, 免费音频压缩'),
-    ('Audio Compressor — Reduce File Size Free | AudioTools', '音频压缩 — 免费在线减小音频文件大小 | AudioTools'),
-    ('"name":"Audio Compressor — AudioTools.dev"', '"name":"音频压缩 — AudioTools.dev"'),
-    ('<h1>Audio Compressor</h1>', '<h1>音频压缩</h1>'),
-    ('<p>Reduce audio file size by adjusting bitrate and sample rate — output as MP3, no upload</p>', '<p>通过调整码率和采样率减小音频文件体积——输出 MP3，无需上传</p>'),
-    ('<p><strong>Drop audio files here</strong>, one or several, or click to browse</p>', '<p><strong>将一个或多个音频文件拖放到此处</strong>，或点击选择</p>'),
-    ('<label class="ctrl-label">Bitrate — lower means smaller file</label>', '<label class="ctrl-label">码率——越低文件越小</label>'),
-    ('>64 kbps — voice / podcast (smallest)</option>', '>64 kbps — 语音 / 播客（最小）</option>'),
-    ('>128 kbps — general purpose (recommended)</option>', '>128 kbps — 通用（推荐）</option>'),
-    ('>192 kbps — high quality music</option>', '>192 kbps — 高品质音乐</option>'),
-    ('>256 kbps — very high quality</option>', '>256 kbps — 极高品质</option>'),
-    ('>320 kbps — maximum quality</option>', '>320 kbps — 最高品质</option>'),
-    ('<label class="ctrl-label">Sample rate</label>', '<label class="ctrl-label">采样率</label>'),
-    ('>Keep original</option>', '>保持原样</option>'),
-    ('>44100 Hz — CD quality</option>', '>44100 Hz — CD 音质</option>'),
-    ('>22050 Hz — smaller, fine for voice</option>', '>22050 Hz — 更小，适合语音</option>'),
-    ('>16000 Hz — smallest, speech only</option>', '>16000 Hz — 最小，仅限语音</option>'),
-    ('<div class="lbl">Original</div>', '<div class="lbl">原始</div>'),
-    ('<div class="lbl">Estimated</div>', '<div class="lbl">预计</div>'),
-    ('>Compress &amp; Download</button>', '>压缩并下载</button>'),
-    ('<div class="progress-text" id="progressText">Compressing…</div>', '<div class="progress-text" id="progressText">压缩中…</div>'),
-    ("progressText.textContent = 'Encoding MP3…';", "progressText.textContent = '正在编码 MP3…';"),
-    ("progressText.textContent = 'Preparing…';", "progressText.textContent = '准备中…';"),
-    ('<p class="result-title">Compressed — <span', '<p class="result-title">压缩完成 — <span'),
-    ('id="downloadBtn" style="width:100%;">Download MP3</button>', 'id="downloadBtn" style="width:100%;">下载 MP3</button>'),
-    ("'% (larger)'", "'%（变大）'"),
-    ("'% vs original'", "'%（相比原文件）'"),
-    ("alert(err.message || 'Compression failed. Please try again.');", "alert(err.message || '压缩失败，请重试。');"),
+    ('"name":"Audio Compressor — AudioTools.dev"',
+     '"name":"音频压缩 — AudioTools.dev"'),
+    ('<p><strong>Drop audio files here</strong>, one or several, or click to browse</p>',
+     '<p><strong>将一个或多个音频文件拖放到此处</strong>，或点击选择</p>'),
+    ('<label class="ctrl-label">Bitrate — lower means smaller file</label>',
+     '<label class="ctrl-label">码率——越低文件越小</label>'),
+    ('>64 kbps — voice / podcast (smallest)</option>',
+     '>64 kbps — 语音 / 播客（最小）</option>'),
+    ('>128 kbps — general purpose (recommended)</option>',
+     '>128 kbps — 通用（推荐）</option>'),
+    ('>192 kbps — high quality music</option>',
+     '>192 kbps — 高品质音乐</option>'),
+    ('>256 kbps — very high quality</option>',
+     '>256 kbps — 极高品质</option>'),
+    ('>320 kbps — maximum quality</option>',
+     '>320 kbps — 最高品质</option>'),
+    ('<label class="ctrl-label">Sample rate</label>',
+     '<label class="ctrl-label">采样率</label>'),
+    ('>Keep original</option>',
+     '>保持原样</option>'),
+    ('>44100 Hz — CD quality</option>',
+     '>44100 Hz — CD 音质</option>'),
+    ('>22050 Hz — smaller, fine for voice</option>',
+     '>22050 Hz — 更小，适合语音</option>'),
+    ('>16000 Hz — smallest, speech only</option>',
+     '>16000 Hz — 最小，仅限语音</option>'),
+    ('<div class="lbl">Original</div>',
+     '<div class="lbl">原始</div>'),
+    ('<div class="lbl">Estimated</div>',
+     '<div class="lbl">预计</div>'),
+    ('>Compress &amp; Download</button>',
+     '>压缩并下载</button>'),
+    ('<div class="progress-text" id="progressText">Compressing…</div>',
+     '<div class="progress-text" id="progressText">压缩中…</div>'),
+    ("progressText.textContent = 'Encoding MP3…';",
+     "progressText.textContent = '正在编码 MP3…';"),
+    ("progressText.textContent = 'Preparing…';",
+     "progressText.textContent = '准备中…';"),
+    ('<p class="result-title">Compressed — <span',
+     '<p class="result-title">压缩完成 — <span'),
+    ('id="downloadBtn" style="width:100%;">Download MP3</button>',
+     'id="downloadBtn" style="width:100%;">下载 MP3</button>'),
+    ("'% (larger)'",
+     "'%（变大）'"),
+    ("'% vs original'",
+     "'%（相比原文件）'"),
+    ("alert(err.message || 'Compression failed. Please try again.');",
+     "alert(err.message || '压缩失败，请重试。');"),
     ("const B = { files: (n) => n + ' files', compress: (n) => 'Compress ' + n + ' files', zip: 'Download all (ZIP)',\n            done: (ok, n) => (ok === n ? n + ' files' : ok + ' of ' + n + ' files') };",
      "const B = { files: (n) => n + ' 个文件', compress: (n) => '压缩 ' + n + ' 个文件', zip: '全部下载（ZIP）',\n            done: (ok, n) => (ok === n ? n + ' 个文件' : n + ' 个中的 ' + ok + ' 个') };"),
     ('<div class="feature-title">Bitrate Control</div><div class="feature-desc">Choose from 64 to 320 kbps for the right size vs quality.</div>',
@@ -289,24 +359,69 @@ def update_hand_made(path, current, en_href):
      '<div class="feature-title">采样率选项</div><div class="feature-desc">降到 22 kHz 或 16 kHz，文件更小。</div>'),
     ('<div class="feature-title">Size Preview</div><div class="feature-desc">See the estimated output size before you compress.</div>',
      '<div class="feature-title">大小预览</div><div class="feature-desc">压缩前即可看到预计的输出大小。</div>'),
-    ('<div class="feature-desc">All compression in your browser. Files never leave your device.</div>', '<div class="feature-desc">所有压缩都在浏览器中完成，文件不会离开您的设备。</div>'),
-    ('<h2>Free Online Audio Compressor</h2>', '<h2>免费在线音频压缩</h2>'),
-    ('<p>Audio Compressor reduces the file size of your audio by re-encoding it to MP3 at a bitrate and sample rate you choose. Perfect for fitting audio into email attachments, messaging apps, or storage limits.</p>',
-     '<p>音频压缩工具按您选择的码率和采样率把音频重新编码为 MP3，从而减小文件体积。非常适合发送邮件附件、通过聊天软件分享，或节省存储空间。</p>'),
-    ('<p>Lossy MP3 compression removes inaudible data to shrink the file. A 44 MB WAV can become a 4 MB MP3 at 128 kbps — roughly a 10x reduction with minimal quality loss for most uses. Higher bitrates (256–320 kbps) preserve more detail for music. Everything runs in your browser, with the LAME MP3 encoder compiled to WebAssembly — nothing is uploaded.</p>',
-     '<p>有损 MP3 压缩会去掉人耳听不到的数据来缩小文件。一个 44 MB 的 WAV 以 128 kbps 编码后约为 4 MB，体积缩小约 10 倍，对大多数用途来说音质损失很小。更高的码率（256–320 kbps）能为音乐保留更多细节。一切都在浏览器中运行，使用编译为 WebAssembly 的 LAME MP3 编码器，不上传任何内容。</p>'),
-    ('<h3>Choosing the Right Bitrate</h3>', '<h3>如何选择码率</h3>'),
-    ('<p>64 kbps — voice recordings and podcasts (smallest files). 128 kbps — general purpose, good quality for most uses. 192 kbps — high quality for music. 320 kbps — maximum quality, indistinguishable from uncompressed for most listeners. Lowering the sample rate to 22 kHz or 16 kHz shrinks speech files further.</p>',
-     '<p>64 kbps：语音录音和播客（文件最小）。128 kbps：通用，适合大多数用途。192 kbps：高品质音乐。320 kbps：最高品质，大多数听众分辨不出与无损的区别。把采样率降到 22 kHz 或 16 kHz，可以让语音文件更小。</p>'),
-    ('<p>Need other edits? Try our <a href="/converter/">Audio Converter</a>, <a href="/audio-trimmer/">Audio Trimmer</a>, <a href="/audio-joiner/">Audio Joiner</a>, or <a href="/volume-booster/">Volume Booster</a>.</p>',
-     '<p>还需要其他处理？试试<a href="/converter/">音频转换器</a>、<a href="/audio-trimmer/">音频剪辑</a>、<a href="/audio-joiner/">音频合并</a>或<a href="/volume-booster/">音量增强器</a>。</p>'),
-    ('<div class="faq-q">How much can I reduce file size?</div><div class="faq-a">Depending on the source, you can reduce WAV files by 5–20x by converting to MP3. A 50 MB WAV becomes ~5 MB at 128 kbps.</div>',
-     '<div class="faq-q">文件能缩小多少？</div><div class="faq-a">视原文件而定，WAV 转为 MP3 后通常可缩小 5–20 倍。一个 50 MB 的 WAV 以 128 kbps 编码约为 5 MB。</div>'),
-    ('<div class="faq-q">Does compression affect quality?</div><div class="faq-a">Lossy compression removes some data. At 192 kbps or higher, most listeners cannot tell the difference from the original.</div>',
-     '<div class="faq-q">压缩会影响音质吗？</div><div class="faq-a">有损压缩会去掉一部分数据。在 192 kbps 及以上，大多数听众听不出与原文件的区别。</div>'),
+    ('<div class="feature-desc">All compression in your browser. Files never leave your device.</div>',
+     '<div class="feature-desc">所有压缩都在浏览器中完成，文件不会离开您的设备。</div>'),
     ('<div class="faq-q">Can I compress several files at once?</div><div class="faq-a">Yes. Drop several files: all of them are compressed with the same settings, and you can download each one or all of them as a ZIP.</div>',
      '<div class="faq-q">可以一次压缩多个文件吗？</div><div class="faq-a">可以。拖入多个文件，它们会使用相同的设置压缩，可以单独下载，也可以打包成 ZIP 一次下载。</div>'),
-    ('<div class="faq-q">Is my audio uploaded?</div><div class="faq-a">No. All compression happens in your browser using the Web Audio API.</div>',
+    ('<title>Compress MP3 &amp; Audio Files Online, Free | AudioTools.dev</title>',
+     '<title>在线压缩 MP3 和音频文件，免费 | AudioTools.dev</title>'),
+    ('Make audio files smaller for email or chat. Pick a bitrate, see the new size first, compress one file or a batch. Free, no upload, runs in your browser.',
+     '让音频文件更小，方便邮件或聊天发送。选择码率，开始前先看新大小，可压缩单个文件或一批文件。免费，无需上传，在浏览器中运行。'),
+    ('Compress MP3 &amp; Audio Files Online, Free',
+     '在线压缩 MP3 和音频文件，免费'),
+    ('compress mp3, reduce audio file size, audio compressor, make audio file smaller, compress audio for email, mp3 compressor online, compress wav to mp3',
+     'MP3压缩, 减小音频文件大小, 音频压缩, 音频变小, 邮件发送音频, 在线MP3压缩, WAV转MP3压缩'),
+    ('<h1>Compress Audio Files</h1>',
+     '<h1>音频压缩</h1>'),
+    ('<p>Make MP3, WAV and other audio files smaller — choose the bitrate, see the size first, no upload</p>',
+     '<p>让 MP3、WAV 等音频文件变小——选择码率，先看大小，无需上传</p>'),
+    ('<h2>Compress MP3 and other audio files online</h2>',
+     '<h2>在线压缩 MP3 等音频文件</h2>'),
+    ('<p>Audio Compressor makes audio files smaller by re-encoding them to MP3 at the bitrate and sample rate you choose. It shows the expected size before you start, handles one file or a whole batch, and runs in your browser with the LAME MP3 encoder compiled to WebAssembly, so nothing is uploaded.</p>',
+     '<p>音频压缩会按您选择的码率和采样率把音频重新编码为 MP3，从而让文件变小。开始前就能看到预计大小，可以处理单个文件或整批文件，并使用编译为 WebAssembly 的 LAME MP3 编码器在浏览器中运行，不上传任何内容。</p>'),
+    ('<h3>How to compress an audio file</h3>',
+     '<h3>如何压缩音频文件</h3>'),
+    ('<li>Drop one or several files on the box above (MP3, WAV, M4A, FLAC, OGG).</li>',
+     '<li>把一个或多个文件拖放到上方的框中（MP3、WAV、M4A、FLAC、OGG）。</li>'),
+    ('<li>Choose a bitrate; for speech, a lower sample rate makes the file smaller still.</li>',
+     '<li>选择码率；如果是语音，降低采样率还能让文件更小。</li>'),
+    ('<li>Check the estimated size.</li>',
+     '<li>查看预计大小。</li>'),
+    ('<li>Click “Compress &amp; Download”. With several files, download each one or all of them as a ZIP.</li>',
+     '<li>点击“压缩并下载”。多个文件时，可单独下载，也可打包成 ZIP 一次下载。</li>'),
+    ('<h3>How small will the file be?</h3>',
+     '<h3>文件会变成多大？</h3>'),
+    ("<p>An MP3's size depends only on its bitrate and length: about 1 MB per minute at 128 kbps and about 0.5 MB per minute at 64 kbps. A 10-minute recording is roughly 10 MB at 128 kbps and 5 MB at 64 kbps.</p>",
+     '<p>MP3 的大小只取决于码率和时长：128 kbps 约每分钟 1 MB，64 kbps 约每分钟 0.5 MB。一段 10 分钟的录音，128 kbps 约 10 MB，64 kbps 约 5 MB。</p>'),
+    ('<h3>Which bitrate to choose</h3>',
+     '<h3>如何选择码率</h3>'),
+    ('<li>64 kbps — voice recordings, lectures and podcasts (smallest files)</li>',
+     '<li>64 kbps — 语音录音、讲座和播客（文件最小）</li>'),
+    ('<li>128 kbps — general purpose, good for most uses</li>',
+     '<li>128 kbps — 通用，适合大多数用途</li>'),
+    ('<li>192 kbps — music in high quality</li>',
+     '<li>192 kbps — 高品质音乐</li>'),
+    ('<li>320 kbps — maximum quality, for when size matters least</li>',
+     '<li>320 kbps — 最高品质，适合不在意大小的时候</li>'),
+    ('<h3>Fit email and chat limits</h3>',
+     '<h3>满足邮件和聊天的大小限制</h3>'),
+    ('<p>Most email services cap attachments at 20–25 MB: roughly 20–25 minutes of audio at 128 kbps, or 40–50 minutes at 64 kbps. For voice, 64 kbps at 22050 Hz keeps speech clear at the smallest size.</p>',
+     '<p>大多数邮箱把附件限制在 20–25 MB：128 kbps 约可容纳 20–25 分钟音频，64 kbps 约 40–50 分钟。如果是语音，64 kbps 加 22050 Hz 能在最小体积下保持清晰。</p>'),
+    ('<h3>WAV to MP3: the biggest saving</h3>',
+     '<h3>WAV 转 MP3：节省最多</h3>'),
+    ('<p>Uncompressed WAV (CD quality) takes about 10.6 MB per minute. Compressing it to MP3 at 128 kbps makes it about 11 times smaller with little audible difference for most uses.</p>',
+     '<p>未压缩的 WAV（CD 音质）每分钟约 10.6 MB。压缩为 128 kbps 的 MP3 后约小 11 倍，对大多数用途来说几乎听不出区别。</p>'),
+    ('<p>Need other edits? Join files first with the <a href="/audio-joiner/">audio joiner</a>, cut silence at the ends with the <a href="/audio-trimmer/">audio trimmer</a>, make a quiet recording louder with the <a href="/volume-booster/">volume booster</a>, or save M4A or FLAC with the <a href="/converter/">audio converter</a>.</p>',
+     '<p>还需要其他处理？可以先用<a href="/audio-joiner/">音频合并</a>把文件连起来，用<a href="/audio-trimmer/">音频剪辑</a>去掉首尾的静音，用<a href="/volume-booster/">音量增强器</a>让小声的录音更响，或用<a href="/converter/">音频转换器</a>保存为 M4A 或 FLAC。</p>'),
+    ('<div class="faq-q">How do I reduce the size of an MP3 file?</div><div class="faq-a">Re-encode it at a lower bitrate. Drop the MP3 here, pick 128 kbps or 64 kbps, and download the smaller file. Lowering the sample rate to 22050 Hz shrinks voice recordings further.</div>',
+     '<div class="faq-q">如何减小 MP3 文件的大小？</div><div class="faq-a">以更低的码率重新编码。把 MP3 拖到这里，选择 128 kbps 或 64 kbps，下载更小的文件。把采样率降到 22050 Hz，语音录音还能更小。</div>'),
+    ('<div class="faq-q">How much smaller will my file be?</div><div class="faq-a">About 1 MB per minute at 128 kbps and 0.5 MB per minute at 64 kbps. A WAV file usually becomes 5 to 20 times smaller. The tool shows the estimate before you compress.</div>',
+     '<div class="faq-q">文件会小多少？</div><div class="faq-a">128 kbps 约每分钟 1 MB，64 kbps 约每分钟 0.5 MB。WAV 文件通常会小 5 到 20 倍。压缩前工具会显示预计大小。</div>'),
+    ('<div class="faq-q">Does compression affect quality?</div><div class="faq-a">Lossy compression removes some data. At 192 kbps or higher, most listeners cannot tell the difference from the original; for speech, 64 kbps is enough.</div>',
+     '<div class="faq-q">压缩会影响音质吗？</div><div class="faq-a">有损压缩会去掉一部分数据。在 192 kbps 及以上，大多数听众听不出与原文件的区别；如果是语音，64 kbps 就够了。</div>'),
+    ('<div class="faq-q">Which sample rate should I use for voice?</div><div class="faq-a">22050 Hz keeps speech clear and makes the file smaller. 16000 Hz is the smallest and still fine for speech, but not for music.</div>',
+     '<div class="faq-q">语音应该用什么采样率？</div><div class="faq-a">22050 Hz 能保持语音清晰，同时让文件更小。16000 Hz 最小，语音仍然可以，但不适合音乐。</div>'),
+    ('<div class="faq-q">Is my audio uploaded?</div><div class="faq-a">No. All compression happens in your browser.</div>',
      '<div class="faq-q">我的音频会被上传吗？</div><div class="faq-a">不会。所有压缩都在您的浏览器中完成。</div>'),
 ],
 'text-to-speech': [
diff --git a/sitemap.xml b/sitemap.xml
index 845ba21..4d3a3d5 100644
--- a/sitemap.xml
+++ b/sitemap.xml
@@ -14,7 +14,7 @@
     </url>
     <url>
         <loc>https://audiotools.dev/voice-to-text/</loc>
-        <lastmod>2026-10-20</lastmod>
+        <lastmod>2026-10-22</lastmod>
         <changefreq>monthly</changefreq>
         <priority>0.9</priority>
     </url>
diff --git a/style.css b/style.css
index 5db09fb..db089e4 100644
--- a/style.css
+++ b/style.css
@@ -109,7 +109,7 @@ h1, h2 { font-stretch: 115%; letter-spacing: -0.015em; }
 
 .seo-content h3 { margin: 24px 0 8px; font-size: 17px; font-weight: 700; color: var(--ink); }
 .seo-content p, .seo-content li { margin: 0 0 12px; font-size: 15px; line-height: 1.7; color: var(--text2); }
-.seo-content ul { margin: 0 0 12px; padding-left: 20px; }
+.seo-content ul, .seo-content ol { margin: 0 0 12px; padding-left: 22px; }
 
 .faq-item { padding: 18px 0; border-top: 1.5px solid var(--ink); }
 .faq-item:last-child { border-bottom: 1.5px solid var(--ink); }
diff --git a/voice-to-text/index.html b/voice-to-text/index.html
index bc99b7d..c421bae 100644
--- a/voice-to-text/index.html
+++ b/voice-to-text/index.html
@@ -14,12 +14,12 @@
       gtag('config', 'G-62ZJNZFRES');
     </script>
 
-    <title>Voice to Text — Free Speech-to-Text Online | AudioTools.dev</title>
+    <title>Voice to Text — Free Private Transcription | AudioTools.dev</title>
 
     <!-- SEO Meta Tags -->
-    <meta name="description" content="Free voice-to-text in 60+ languages: live dictation, or transcribe audio files privately with Whisper running on your device. No sign-up, no upload.">
+    <meta name="description" content="Transcribe voice messages, recordings and audio files to text for free. Whisper runs in your browser, so nothing is uploaded. Live dictation in 60+ languages.">
     <meta name="keywords"
-          content="voice to text, speech to text, transcription online, speech recognition, voice transcription free, dictation, convert speech to text, audio to text">
+          content="voice to text, audio to text, transcribe audio to text free, speech to text online, voice message to text, mp3 to text, whisper online, dictation">
     <meta name="author" content="Roman Gordienko">
     <meta name="robots" content="index, follow, max-snippet:-1, max-image-preview:large">
     <link rel="canonical" href="https://audiotools.dev/voice-to-text/">
@@ -27,15 +27,15 @@
     <meta property="og:site_name" content="AudioTools.dev">
     <meta property="og:locale" content="en_US">
     <meta property="og:url" content="https://audiotools.dev/voice-to-text/">
-    <meta property="og:title" content="Voice to Text — Free Online Speech-to-Text Transcription">
-    <meta property="og:description" content="Free voice-to-text in 60+ languages: live dictation, or transcribe audio files privately with Whisper running on your device. No sign-up, no upload.">
+    <meta property="og:title" content="Voice to Text — Free, Private Transcription in Your Browser">
+    <meta property="og:description" content="Transcribe voice messages, recordings and audio files to text for free. Whisper runs in your browser, so nothing is uploaded. Live dictation in 60+ languages.">
     <meta property="og:image" content="https://audiotools.dev/og/voice-to-text.png">
     <meta property="og:image:width" content="1200">
     <meta property="og:image:height" content="630">
-    <meta property="og:image:alt" content="Voice to Text — Free Online Speech-to-Text Transcription">
+    <meta property="og:image:alt" content="Voice to Text — Free, Private Transcription in Your Browser">
     <meta name="twitter:card" content="summary_large_image">
-    <meta name="twitter:title" content="Voice to Text — Free Online Speech-to-Text Transcription">
-    <meta name="twitter:description" content="Free voice-to-text in 60+ languages: live dictation, or transcribe audio files privately with Whisper running on your device. No sign-up, no upload.">
+    <meta name="twitter:title" content="Voice to Text — Free, Private Transcription in Your Browser">
+    <meta name="twitter:description" content="Transcribe voice messages, recordings and audio files to text for free. Whisper runs in your browser, so nothing is uploaded. Live dictation in 60+ languages.">
     <meta name="twitter:image" content="https://audiotools.dev/og/voice-to-text.png">
 
     <!-- Favicon -->
@@ -84,32 +84,38 @@
     {
         "@context": "https://schema.org",
         "@type": "HowTo",
-        "name": "How to transcribe speech to text online",
-        "description": "Use Audio Tools Voice to Text to convert spoken words into written text directly in your browser.",
+        "name": "How to transcribe an audio file to text",
+        "description": "Transcribe an audio file or voice message to text with Whisper running in your browser.",
         "step": [
             {
                 "@type": "HowToStep",
                 "position": 1,
-                "name": "Select language",
-                "text": "Choose your spoken language from the dropdown menu. Over 60 languages are supported."
+                "name": "Choose the language",
+                "text": "Choose the spoken language at the top."
             },
             {
                 "@type": "HowToStep",
                 "position": 2,
-                "name": "Click Start Recording",
-                "text": "Press the Start Recording button and allow microphone access when prompted."
+                "name": "Pick a model",
+                "text": "In Private mode, pick a model: Tiny is faster, Base is more accurate."
             },
             {
                 "@type": "HowToStep",
                 "position": 3,
-                "name": "Speak clearly",
-                "text": "Speak into your microphone. Text will appear in real-time as you speak."
+                "name": "Choose the file",
+                "text": "Click Transcribe file and choose an audio or video file, or Record & transcribe to use the microphone."
             },
             {
                 "@type": "HowToStep",
                 "position": 4,
-                "name": "Export your text",
-                "text": "Copy the transcription to clipboard or download as a TXT file."
+                "name": "Wait for the model once",
+                "text": "The first time, the model downloads once (about 45–80 MB) and is then kept by your browser."
+            },
+            {
+                "@type": "HowToStep",
+                "position": 5,
+                "name": "Copy or download the text",
+                "text": "Copy the text or download it as a .txt file."
             }
         ]
     }
@@ -409,12 +415,36 @@
         "@context": "https://schema.org",
         "@type": "FAQPage",
         "mainEntity": [
+            {
+                "@type": "Question",
+                "name": "How do I convert a voice recording to text?",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "Choose the language, click “Transcribe file” in Private mode and pick the recording. Whisper transcribes it in your browser, then you can copy the text or download it as a.txt file."
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "Can I transcribe WhatsApp or Telegram voice messages?",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "Yes. Save the voice message from the chat (an.opus or.ogg file) and open it with “Transcribe file”. It is transcribed on your device and never uploaded."
+                }
+            },
             {
                 "@type": "Question",
                 "name": "Is my voice data sent to a server?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "The Web Speech API requires an internet connection and sends audio to the browser vendor (Google for Chrome, Apple for Safari) for processing. Your audio is not stored on our servers — we have no backend. In Private mode, speech is transcribed by the Whisper model running in your browser, so your audio never leaves your device."
+                    "text": "Not in Private mode: Whisper runs in your browser and your audio never leaves your device. Live dictation uses the browser's speech engine, which in Chrome and Safari sends audio to Google or Apple. AudioTools.dev has no backend and stores nothing."
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "Is it free? Is there a length limit?",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "It is free with no limits. Long recordings simply take longer, depending on your device and the model you choose."
                 }
             },
             {
@@ -422,7 +452,7 @@
                 "name": "Which languages are supported?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "Over 60 languages including English, Spanish, French, German, Chinese, Japanese, Russian, Arabic, Hindi, Portuguese, and many more. The available languages depend on your browser."
+                    "text": "Private mode (Whisper) understands about 100 languages. Live dictation supports 60+ languages; the list depends on your browser."
                 }
             },
             {
@@ -430,7 +460,7 @@
                 "name": "Does it work on mobile?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "Yes. Voice to text works on Chrome for Android and Safari for iOS. Tap the microphone button and speak — results appear in real-time."
+                    "text": "Yes. Both modes work in Chrome on Android and Safari on iPhone. Private mode downloads the model once (about 45–80 MB), so use Wi-Fi the first time."
                 }
             },
             {
@@ -438,7 +468,7 @@
                 "name": "How accurate is the transcription?",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "Accuracy depends on your browser's speech recognition engine. Chrome (powered by Google) provides the best accuracy for most languages. Clear speech in a quiet environment gives the best results."
+                    "text": "For clear speech, Whisper Base is accurate enough for notes and drafts; Tiny is faster but makes more mistakes. Background noise, music and several people talking at once lower accuracy."
                 }
             }
         ]
@@ -465,7 +495,7 @@
     <section class="hero">
         <svg class="hero-glyph" viewBox="0 0 160 56" aria-hidden="true"><path class="g-ink" d="M4 28 C12 10 20 10 28 28 S44 46 52 28 S68 10 76 28"/><path class="g-acc" d="M98 16 H156 M98 28 H148 M98 40 H128"/></svg>
             <h1>Voice to Text</h1>
-        <p>Free online speech-to-text — live dictation in 60+ languages, or private on-device transcription of audio files</p>
+        <p>Turn recordings, voice messages and live speech into text — free, with private on-device transcription</p>
     </section>
 
     <!-- Browser compatibility warning -->
@@ -604,69 +634,71 @@ <h2>Private mode — Whisper on your device</h2>
 
     <!-- SEO Content -->
     <section class="seo-content">
-        <h2>Free Online Voice to Text Transcription</h2>
-        <p>
-            Audio Tools Voice to Text is a free online speech-to-text transcription tool that converts your
-            spoken words into written text in real-time using your browser's Web Speech Recognition API — no software
-            installation and no account registration. Private mode transcribes audio files and recordings with the
-            Whisper speech model running entirely in your browser, so the audio is never uploaded anywhere.
-        </p>
-
-        <h3>How It Works</h3>
-        <p>
-            Simply select your language, click "Start Recording", and speak into your microphone. The tool uses
-            your browser's built-in speech recognition engine to transcribe your speech in real-time. You can see
-            the text appearing as you speak, and when you're done, copy it to your clipboard or download it as a
-            text file.
-        </p>
-
-        <h3>Supported Languages</h3>
-        <p>
-            The Voice to Text tool supports over 60 languages and regional dialects, including English (US/UK),
-            Russian, German, French, Spanish, Italian, Portuguese, Chinese (Simplified/Traditional), Japanese,
-            Korean, Arabic, Hindi, and many more European and Asian languages.
-        </p>
-
-        <h3>Use Cases</h3>
+        <h2>Transcribe audio to text for free</h2>
+        <p>Voice to Text turns speech into text in two ways. <strong>Private mode</strong> transcribes audio files and recordings with the Whisper speech model running in your browser, so the audio never leaves your device. <strong>Live dictation</strong> writes down what you say in real time using your browser's speech engine. Both are free, with no account and no length limit.</p>
+
+        <h3>How to transcribe an audio file</h3>
+        <ol>
+            <li>Choose the spoken language at the top.</li>
+            <li>In Private mode, pick a model: Tiny is faster, Base is more accurate.</li>
+            <li>Click “Transcribe file” and choose an audio or video file (MP3, WAV, M4A, OGG/Opus voice messages, MP4…), or click “Record &amp; transcribe” to use the microphone.</li>
+            <li>The first time, the model downloads once (about 45–80 MB) and is then kept by your browser.</li>
+            <li>Copy the text or download it as a .txt file.</li>
+        </ol>
+
+        <h3>Voice messages to text</h3>
+        <p>Save a voice message from WhatsApp or Telegram (an .opus or .ogg file) and open it with “Transcribe file”. It is transcribed on your device, which matters for private conversations.</p>
+
+        <h3>Private mode or live dictation?</h3>
+        <ul>
+            <li><strong>Private mode</strong> — for files and recordings. Runs on your device and works offline once the model is downloaded. Long recordings take a while on slower phones.</li>
+            <li><strong>Live dictation</strong> — text appears as you speak. Uses your browser's speech engine, which in Chrome and Safari may send the audio to Google or Apple, and needs an internet connection.</li>
+        </ul>
+
+        <h3>Supported languages</h3>
+        <p>Whisper understands about 100 languages, including English, Chinese, Spanish, Russian, German, French, Japanese, Korean, Arabic, Hindi and Portuguese. Live dictation supports 60+ languages and regional variants; the exact list depends on your browser.</p>
+
+        <h3>Use cases</h3>
         <ul>
-            <li>Taking notes during meetings and lectures</li>
-            <li>Dictating emails, messages, and documents</li>
-            <li>Creating subtitles and captions for videos</li>
-            <li>Transcribing interviews and podcasts</li>
-            <li>Accessibility — hands-free text input</li>
-            <li>Language learning and pronunciation practice</li>
+            <li>Notes from meetings, lectures and interviews</li>
+            <li>Voice messages you would rather read</li>
+            <li>Dictating emails, messages and documents</li>
+            <li>A first draft of subtitles for a video</li>
+            <li>Hands-free text input</li>
         </ul>
 
-        <h3>Privacy & Security</h3>
-        <p>
-            Live dictation uses your browser's speech recognition engine, which may send audio to the browser
-            vendor (Google in Chrome, Apple in Safari). Private mode runs the Whisper model on your device: the
-            model is downloaded once from Hugging Face, and your audio never leaves the browser. AudioTools.dev has
-            no backend — we never receive your audio or transcriptions.
-        </p>
-
-        <h3>Browser Compatibility</h3>
-        <p>
-            Voice to Text works best in Google Chrome, Microsoft Edge, and Safari. These browsers have built-in
-            support for the Web Speech Recognition API. Firefox has limited support for speech recognition.
-            For the best experience, we recommend using the latest version of Chrome or Edge.
-        </p>
+        <h3>Privacy</h3>
+        <p>Private mode runs the Whisper model on your device: the model is downloaded once from Hugging Face, and your audio never leaves the browser. Live dictation uses the browser's speech engine, which may send audio to the browser vendor. AudioTools.dev has no backend — we never receive your audio or transcriptions.</p>
+
+        <h3>Browser compatibility</h3>
+        <p>Private mode works in current versions of Chrome, Edge, Firefox and Safari. Live dictation works in Chrome, Edge and Safari; Firefox does not support it.</p>
+
+        <p>Need the reverse? <a href="/text-to-speech/">Text to speech</a> reads text aloud. To get the sound out of a video or shrink a long recording first, use the <a href="/converter/">audio converter</a> or the <a href="/audio-compressor/">audio compressor</a>.</p>
     </section>
 
     <section class="seo-content" style="margin-top: 0;">
         <h2>Frequently Asked Questions</h2>
-        
+
+        <h3>How do I convert a voice recording to text?</h3>
+        <p>Choose the language, click “Transcribe file” in Private mode and pick the recording. Whisper transcribes it in your browser, then you can copy the text or download it as a .txt file.</p>
+
+        <h3>Can I transcribe WhatsApp or Telegram voice messages?</h3>
+        <p>Yes. Save the voice message from the chat (an .opus or .ogg file) and open it with “Transcribe file”. It is transcribed on your device and never uploaded.</p>
+
         <h3>Is my voice data sent to a server?</h3>
-        <p>The Web Speech API requires an internet connection and sends audio to the browser vendor (Google for Chrome, Apple for Safari) for processing. Your audio is not stored on our servers — we have no backend. In Private mode, speech is transcribed by the Whisper model running in your browser, so your audio never leaves your device.</p>
-        
+        <p>Not in Private mode: Whisper runs in your browser and your audio never leaves your device. Live dictation uses the browser's speech engine, which in Chrome and Safari sends audio to Google or Apple. AudioTools.dev has no backend and stores nothing.</p>
+
+        <h3>Is it free? Is there a length limit?</h3>
+        <p>It is free with no limits. Long recordings simply take longer, depending on your device and the model you choose.</p>
+
         <h3>Which languages are supported?</h3>
-        <p>Over 60 languages including English, Spanish, French, German, Chinese, Japanese, Russian, Arabic, Hindi, Portuguese, and many more. The available languages depend on your browser.</p>
-        
+        <p>Private mode (Whisper) understands about 100 languages. Live dictation supports 60+ languages; the list depends on your browser.</p>
+
         <h3>Does it work on mobile?</h3>
-        <p>Yes. Voice to text works on Chrome for Android and Safari for iOS. Tap the microphone button and speak — results appear in real-time.</p>
-        
+        <p>Yes. Both modes work in Chrome on Android and Safari on iPhone. Private mode downloads the model once (about 45–80 MB), so use Wi-Fi the first time.</p>
+
         <h3>How accurate is the transcription?</h3>
-        <p>Accuracy depends on your browser's speech recognition engine. Chrome (powered by Google) provides the best accuracy for most languages. Clear speech in a quiet environment gives the best results.</p>
+        <p>For clear speech, Whisper Base is accurate enough for notes and drafts; Tiny is faster but makes more mistakes. Background noise, music and several people talking at once lower accuracy.</p>
     </section>
 </div>
 
diff --git a/zh/audio-compressor/index.html b/zh/audio-compressor/index.html
index 939b9b5..acfbcf9 100644
--- a/zh/audio-compressor/index.html
+++ b/zh/audio-compressor/index.html
@@ -13,9 +13,9 @@
       gtag('js', new Date());
       gtag('config', 'G-62ZJNZFRES');
     </script>
-    <title>音频压缩 — 免费在线减小音频文件大小 | AudioTools.dev</title>
-    <meta name="description" content="免费在线压缩音频：调整码率和采样率，减小 MP3、WAV 文件体积。无需上传，在浏览器中运行。">
-    <meta name="keywords" content="音频压缩, 减小音频文件大小, 在线压缩MP3, 音频变小, 降低码率, 压缩WAV, 免费音频压缩">
+    <title>在线压缩 MP3 和音频文件，免费 | AudioTools.dev</title>
+    <meta name="description" content="让音频文件更小，方便邮件或聊天发送。选择码率，开始前先看新大小，可压缩单个文件或一批文件。免费，无需上传，在浏览器中运行。">
+    <meta name="keywords" content="MP3压缩, 减小音频文件大小, 音频压缩, 音频变小, 邮件发送音频, 在线MP3压缩, WAV转MP3压缩">
     <link rel="canonical" href="https://audiotools.dev/zh/audio-compressor/">
     <link rel="alternate" hreflang="en" href="https://audiotools.dev/audio-compressor/">
     <link rel="alternate" hreflang="zh" href="https://audiotools.dev/zh/audio-compressor/">
@@ -24,22 +24,22 @@
     <meta property="og:site_name" content="AudioTools.dev">
     <meta property="og:locale" content="zh_CN">
     <meta property="og:url" content="https://audiotools.dev/zh/audio-compressor/">
-    <meta property="og:title" content="音频压缩 — 免费在线减小音频文件大小 | AudioTools">
-    <meta property="og:description" content="免费在线压缩音频：调整码率和采样率，减小 MP3、WAV 文件体积。无需上传，在浏览器中运行。">
+    <meta property="og:title" content="在线压缩 MP3 和音频文件，免费">
+    <meta property="og:description" content="让音频文件更小，方便邮件或聊天发送。选择码率，开始前先看新大小，可压缩单个文件或一批文件。免费，无需上传，在浏览器中运行。">
     <meta property="og:image" content="https://audiotools.dev/og/zh-audio-compressor.png">
     <meta property="og:image:width" content="1200">
     <meta property="og:image:height" content="630">
-    <meta property="og:image:alt" content="音频压缩 — 免费在线减小音频文件大小 | AudioTools">
+    <meta property="og:image:alt" content="在线压缩 MP3 和音频文件，免费">
     <meta name="twitter:card" content="summary_large_image">
-    <meta name="twitter:title" content="音频压缩 — 免费在线减小音频文件大小 | AudioTools">
-    <meta name="twitter:description" content="免费在线压缩音频：调整码率和采样率，减小 MP3、WAV 文件体积。无需上传，在浏览器中运行。">
+    <meta name="twitter:title" content="在线压缩 MP3 和音频文件，免费">
+    <meta name="twitter:description" content="让音频文件更小，方便邮件或聊天发送。选择码率，开始前先看新大小，可压缩单个文件或一批文件。免费，无需上传，在浏览器中运行。">
     <meta name="twitter:image" content="https://audiotools.dev/og/zh-audio-compressor.png">
     <meta name="robots" content="index, follow, max-snippet:-1, max-image-preview:large">
     <link rel="icon" type="image/svg+xml" href="/favicon.svg">
     <link rel="icon" type="image/x-icon" href="/favicon.ico">
     <link rel="apple-touch-icon" href="/apple-touch-icon.png">
     <script type="application/ld+json">
-    {"@context":"https://schema.org","@type":"WebApplication","inLanguage": "zh-CN","name":"音频压缩 — AudioTools.dev","url":"https://audiotools.dev/zh/audio-compressor/","description":"免费在线压缩音频：调整码率和采样率，减小 MP3、WAV 文件体积。无需上传，在浏览器中运行。","applicationCategory":"MultimediaApplication","operatingSystem":"Any","isAccessibleForFree":true,"offers":{"@type":"Offer","price":"0","priceCurrency":"USD"}}
+    {"@context":"https://schema.org","@type":"WebApplication","inLanguage": "zh-CN","name":"音频压缩 — AudioTools.dev","url":"https://audiotools.dev/zh/audio-compressor/","description":"让音频文件更小，方便邮件或聊天发送。选择码率，开始前先看新大小，可压缩单个文件或一批文件。免费，无需上传，在浏览器中运行。","applicationCategory":"MultimediaApplication","operatingSystem":"Any","isAccessibleForFree":true,"offers":{"@type":"Offer","price":"0","priceCurrency":"USD"}}
     </script>
     <script type="application/ld+json">
     {
@@ -48,10 +48,18 @@
         "mainEntity": [
             {
                 "@type": "Question",
-                "name": "文件能缩小多少？",
+                "name": "如何减小 MP3 文件的大小？",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "视原文件而定，WAV 转为 MP3 后通常可缩小 5–20 倍。一个 50 MB 的 WAV 以 128 kbps 编码约为 5 MB。"
+                    "text": "以更低的码率重新编码。把 MP3 拖到这里，选择 128 kbps 或 64 kbps，下载更小的文件。把采样率降到 22050 Hz，语音录音还能更小。"
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "文件会小多少？",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "128 kbps 约每分钟 1 MB，64 kbps 约每分钟 0.5 MB。WAV 文件通常会小 5 到 20 倍。压缩前工具会显示预计大小。"
                 }
             },
             {
@@ -59,7 +67,7 @@
                 "name": "压缩会影响音质吗？",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "有损压缩会去掉一部分数据。在 192 kbps 及以上，大多数听众听不出与原文件的区别。"
+                    "text": "有损压缩会去掉一部分数据。在 192 kbps 及以上，大多数听众听不出与原文件的区别；如果是语音，64 kbps 就够了。"
                 }
             },
             {
@@ -70,6 +78,14 @@
                     "text": "可以。拖入多个文件，它们会使用相同的设置压缩，可以单独下载，也可以打包成 ZIP 一次下载。"
                 }
             },
+            {
+                "@type": "Question",
+                "name": "语音应该用什么采样率？",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "22050 Hz 能保持语音清晰，同时让文件更小。16000 Hz 最小，语音仍然可以，但不适合音乐。"
+                }
+            },
             {
                 "@type": "Question",
                 "name": "我的音频会被上传吗？",
@@ -154,7 +170,7 @@
         <section class="hero">
             <svg class="hero-glyph" viewBox="0 0 160 56" aria-hidden="true"><polyline class="g-ink" style="stroke-width:1.6" points="4,28 7,14 10,40 13,18 16,36 19,10 22,44 25,20 28,34 31,12 34,42 37,22 40,30 43,16 46,38 49,24 52,32 55,20 58,28"/><polyline class="g-acc" points="72,28 88,14 104,40 120,16 136,38 152,24 156,28"/></svg>
             <h1>音频压缩</h1>
-            <p>通过调整码率和采样率减小音频文件体积——输出 MP3，无需上传</p>
+            <p>让 MP3、WAV 等音频文件变小——选择码率，先看大小，无需上传</p>
         </section>
 
         <div class="tool-area">
@@ -226,20 +242,38 @@ <h1>音频压缩</h1>
         </div>
 
         <section class="seo-content">
-            <h2>免费在线音频压缩</h2>
-            <p>音频压缩工具按您选择的码率和采样率把音频重新编码为 MP3，从而减小文件体积。非常适合发送邮件附件、通过聊天软件分享，或节省存储空间。</p>
-            <h3>工作原理</h3>
-            <p>有损 MP3 压缩会去掉人耳听不到的数据来缩小文件。一个 44 MB 的 WAV 以 128 kbps 编码后约为 4 MB，体积缩小约 10 倍，对大多数用途来说音质损失很小。更高的码率（256–320 kbps）能为音乐保留更多细节。一切都在浏览器中运行，使用编译为 WebAssembly 的 LAME MP3 编码器，不上传任何内容。</p>
+            <h2>在线压缩 MP3 等音频文件</h2>
+            <p>音频压缩会按您选择的码率和采样率把音频重新编码为 MP3，从而让文件变小。开始前就能看到预计大小，可以处理单个文件或整批文件，并使用编译为 WebAssembly 的 LAME MP3 编码器在浏览器中运行，不上传任何内容。</p>
+            <h3>如何压缩音频文件</h3>
+            <ol>
+                <li>把一个或多个文件拖放到上方的框中（MP3、WAV、M4A、FLAC、OGG）。</li>
+                <li>选择码率；如果是语音，降低采样率还能让文件更小。</li>
+                <li>查看预计大小。</li>
+                <li>点击“压缩并下载”。多个文件时，可单独下载，也可打包成 ZIP 一次下载。</li>
+            </ol>
+            <h3>文件会变成多大？</h3>
+            <p>MP3 的大小只取决于码率和时长：128 kbps 约每分钟 1 MB，64 kbps 约每分钟 0.5 MB。一段 10 分钟的录音，128 kbps 约 10 MB，64 kbps 约 5 MB。</p>
             <h3>如何选择码率</h3>
-            <p>64 kbps：语音录音和播客（文件最小）。128 kbps：通用，适合大多数用途。192 kbps：高品质音乐。320 kbps：最高品质，大多数听众分辨不出与无损的区别。把采样率降到 22 kHz 或 16 kHz，可以让语音文件更小。</p>
-            <p>还需要其他处理？试试<a href="/zh/converter/">音频转换器</a>、<a href="/audio-trimmer/">音频剪辑</a>、<a href="/zh/audio-joiner/">音频合并</a>或<a href="/zh/volume-booster/">音量增强器</a>。</p>
+            <ul>
+                <li>64 kbps — 语音录音、讲座和播客（文件最小）</li>
+                <li>128 kbps — 通用，适合大多数用途</li>
+                <li>192 kbps — 高品质音乐</li>
+                <li>320 kbps — 最高品质，适合不在意大小的时候</li>
+            </ul>
+            <h3>满足邮件和聊天的大小限制</h3>
+            <p>大多数邮箱把附件限制在 20–25 MB：128 kbps 约可容纳 20–25 分钟音频，64 kbps 约 40–50 分钟。如果是语音，64 kbps 加 22050 Hz 能在最小体积下保持清晰。</p>
+            <h3>WAV 转 MP3：节省最多</h3>
+            <p>未压缩的 WAV（CD 音质）每分钟约 10.6 MB。压缩为 128 kbps 的 MP3 后约小 11 倍，对大多数用途来说几乎听不出区别。</p>
+            <p>还需要其他处理？可以先用<a href="/zh/audio-joiner/">音频合并</a>把文件连起来，用<a href="/audio-trimmer/">音频剪辑</a>去掉首尾的静音，用<a href="/zh/volume-booster/">音量增强器</a>让小声的录音更响，或用<a href="/zh/converter/">音频转换器</a>保存为 M4A 或 FLAC。</p>
         </section>
 
         <section class="faq">
             <h2>常见问题</h2>
-            <div class="faq-item"><div class="faq-q">文件能缩小多少？</div><div class="faq-a">视原文件而定，WAV 转为 MP3 后通常可缩小 5–20 倍。一个 50 MB 的 WAV 以 128 kbps 编码约为 5 MB。</div></div>
-            <div class="faq-item"><div class="faq-q">压缩会影响音质吗？</div><div class="faq-a">有损压缩会去掉一部分数据。在 192 kbps 及以上，大多数听众听不出与原文件的区别。</div></div>
+            <div class="faq-item"><div class="faq-q">如何减小 MP3 文件的大小？</div><div class="faq-a">以更低的码率重新编码。把 MP3 拖到这里，选择 128 kbps 或 64 kbps，下载更小的文件。把采样率降到 22050 Hz，语音录音还能更小。</div></div>
+            <div class="faq-item"><div class="faq-q">文件会小多少？</div><div class="faq-a">128 kbps 约每分钟 1 MB，64 kbps 约每分钟 0.5 MB。WAV 文件通常会小 5 到 20 倍。压缩前工具会显示预计大小。</div></div>
+            <div class="faq-item"><div class="faq-q">压缩会影响音质吗？</div><div class="faq-a">有损压缩会去掉一部分数据。在 192 kbps 及以上，大多数听众听不出与原文件的区别；如果是语音，64 kbps 就够了。</div></div>
             <div class="faq-item"><div class="faq-q">可以一次压缩多个文件吗？</div><div class="faq-a">可以。拖入多个文件，它们会使用相同的设置压缩，可以单独下载，也可以打包成 ZIP 一次下载。</div></div>
+            <div class="faq-item"><div class="faq-q">语音应该用什么采样率？</div><div class="faq-a">22050 Hz 能保持语音清晰，同时让文件更小。16000 Hz 最小，语音仍然可以，但不适合音乐。</div></div>
             <div class="faq-item"><div class="faq-q">我的音频会被上传吗？</div><div class="faq-a">不会。所有压缩都在您的浏览器中完成。</div></div>
         </section>
     </div>
diff --git a/zh/audio-joiner/index.html b/zh/audio-joiner/index.html
index 7275872..74fc808 100644
--- a/zh/audio-joiner/index.html
+++ b/zh/audio-joiner/index.html
@@ -13,9 +13,9 @@
       gtag('js', new Date());
       gtag('config', 'G-62ZJNZFRES');
     </script>
-    <title>音频合并 — 免费在线合并 MP3、WAV 文件 | AudioTools.dev</title>
-    <meta name="description" content="免费在线音频合并工具：在浏览器中合并、拼接 MP3、WAV、FLAC 文件。无需上传，无需注册，可在音轨之间添加淡入淡出。">
-    <meta name="keywords" content="音频合并, 在线合并音频, MP3合并, 拼接音频文件, 音频拼接, 合并WAV, 免费音频合并">
+    <title>音频合并 — 免费在线合并 MP3 文件 | AudioTools.dev</title>
+    <meta name="description" content="在浏览器中把 MP3、WAV、M4A 和语音消息合并为一个文件。可调整顺序、添加淡入淡出，保存为 MP3 或 WAV。免费，无需上传，无需注册。">
+    <meta name="keywords" content="MP3合并, 音频合并, 合并音频文件, 在线合并MP3, 拼接音频, 合并语音消息, 音频拼接工具, 免费合并MP3">
     <link rel="canonical" href="https://audiotools.dev/zh/audio-joiner/">
     <link rel="alternate" hreflang="en" href="https://audiotools.dev/audio-joiner/">
     <link rel="alternate" hreflang="zh" href="https://audiotools.dev/zh/audio-joiner/">
@@ -24,22 +24,22 @@
     <meta property="og:site_name" content="AudioTools.dev">
     <meta property="og:locale" content="zh_CN">
     <meta property="og:url" content="https://audiotools.dev/zh/audio-joiner/">
-    <meta property="og:title" content="音频合并 — 免费在线合并 MP3、WAV 文件 | AudioTools">
-    <meta property="og:description" content="免费在线音频合并工具：在浏览器中合并 MP3、WAV、FLAC 文件。无需上传，可添加淡入淡出。">
+    <meta property="og:title" content="音频合并 — 免费在线合并 MP3 文件">
+    <meta property="og:description" content="在浏览器中把 MP3、WAV、M4A 和语音消息合并为一个文件。可调整顺序、添加淡入淡出，保存为 MP3 或 WAV。免费，无需上传，无需注册。">
     <meta property="og:image" content="https://audiotools.dev/og/zh-audio-joiner.png">
     <meta property="og:image:width" content="1200">
     <meta property="og:image:height" content="630">
-    <meta property="og:image:alt" content="音频合并 — 免费在线合并 MP3、WAV 文件 | AudioTools">
+    <meta property="og:image:alt" content="音频合并 — 免费在线合并 MP3 文件">
     <meta name="twitter:card" content="summary_large_image">
-    <meta name="twitter:title" content="音频合并 — 免费在线合并 MP3、WAV 文件 | AudioTools">
-    <meta name="twitter:description" content="免费在线音频合并工具：在浏览器中合并 MP3、WAV、FLAC 文件。无需上传，可添加淡入淡出。">
+    <meta name="twitter:title" content="音频合并 — 免费在线合并 MP3 文件">
+    <meta name="twitter:description" content="在浏览器中把 MP3、WAV、M4A 和语音消息合并为一个文件。可调整顺序、添加淡入淡出，保存为 MP3 或 WAV。免费，无需上传，无需注册。">
     <meta name="twitter:image" content="https://audiotools.dev/og/zh-audio-joiner.png">
     <meta name="robots" content="index, follow, max-snippet:-1, max-image-preview:large">
     <link rel="icon" type="image/svg+xml" href="/favicon.svg">
     <link rel="icon" type="image/x-icon" href="/favicon.ico">
     <link rel="apple-touch-icon" href="/apple-touch-icon.png">
     <script type="application/ld+json">
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+    {"@context":"https://schema.org","@type":"WebApplication","inLanguage": "zh-CN","name":"音频合并 — AudioTools.dev","url":"https://audiotools.dev/zh/audio-joiner/","description":"在浏览器中把 MP3、WAV、M4A 和语音消息合并为一个文件。可调整顺序、添加淡入淡出，保存为 MP3 或 WAV。免费，无需上传，无需注册。","applicationCategory":"MultimediaApplication","operatingSystem":"Any","isAccessibleForFree":true,"offers":{"@type":"Offer","price":"0","priceCurrency":"USD"}}
     </script>
     <script type="application/ld+json">
     {
@@ -48,10 +48,10 @@
         "mainEntity": [
             {
                 "@type": "Question",
-                "name": "如何在线合并音频文件？",
+                "name": "如何把多个 MP3 合并成一个？",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "添加文件，排好顺序，可选添加淡入淡出，然后点击“合并并下载”，即可得到一个合并后的文件。"
+                    "text": "添加 MP3 文件，排好顺序，可选设置淡入淡出，然后点击“合并并下载”。您会得到一个在浏览器中生成的 MP3 或 WAV 文件。"
                 }
             },
             {
@@ -59,7 +59,31 @@
                 "name": "可以合并不同格式的文件吗？",
                 "acceptedAnswer": {
                     "@type": "Answer",
-                    "text": "可以。MP3、WAV、FLAC、OGG 可混合使用。浏览器会分别解码每个文件，合并结果保存为 MP3 或 WAV。"
+                    "text": "可以。MP3、WAV、M4A、FLAC、OGG 和 Opus 可以在一次合并中混用。每个文件由浏览器解码，结果保存为 MP3 或 WAV。"
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "可以合并 WhatsApp 或 Telegram 的语音消息吗？",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "可以。从聊天中保存语音消息（.opus 或.ogg 文件），然后添加到这里。Chrome、Edge 和 Firefox 可以播放这类文件，部分旧版 Safari 不行。"
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "合并会降低音质吗？",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "保存为 WAV 时，解码后的音频保持不变。保存为 MP3 时会以 192 kbps 重新编码，对语音和大多数音乐来说听起来与原文件相同。"
+                }
+            },
+            {
+                "@type": "Question",
+                "name": "文件数量有限制吗？",
+                "acceptedAnswer": {
+                    "@type": "Answer",
+                    "text": "没有固定限制。唯一的限制是设备内存，因为合并时所有音轨都保存在内存中。"
                 }
             },
             {
@@ -149,7 +173,7 @@
         <section class="hero">
             <svg class="hero-glyph" viewBox="0 0 160 56" aria-hidden="true"><polyline class="g-ink" points="4,28 10,18 16,38 22,14 28,42 34,20 40,36 46,24 52,30 58,28"/><polyline class="g-ink" points="102,28 108,22 114,34 120,12 126,44 132,18 138,38 144,16 150,40 156,28"/><path class="g-acc" d="M58 28 C72 28 72 14 80 14 S88 28 102 28 M58 28 C72 28 72 42 80 42 S88 28 102 28"/></svg>
             <h1>音频合并</h1>
-            <p>把多个音频文件合并为一个——可调整顺序、添加淡入淡出，无需上传</p>
+            <p>把 MP3、语音消息等音频合并成一条音轨——可调整顺序、淡入淡出，无需上传</p>
         </section>
 
         <div class="tool-area">
@@ -198,21 +222,39 @@ <h1>音频合并</h1>
         </div>
 
         <section class="seo-content">
-            <h2>免费在线音频合并与拼接</h2>
-            <p>音频合并工具直接在浏览器中把多个音频文件合成一条音轨。无论是合并播客片段、拼接音乐，还是连接语音录音，都不需要把文件上传到任何服务器。</p>
-            <h3>工作原理</h3>
-            <p>工具使用 Web Audio API 把每个文件解码为原始 PCM，按您设定的顺序拼接，可选在相邻音轨之间添加淡入淡出，再编码为 MP3 或 WAV。所有处理都在浏览器中完成，不涉及服务器。</p>
-            <h3>调整顺序与淡入淡出</h3>
-            <p>拖动音轨即可调整顺序，也可以使用上下箭头。淡入淡出最长可设为 3 秒，让上一条音轨的结尾平滑过渡到下一条的开头，适合音乐串烧和无缝的播客剪辑。设为 0 则直接首尾相接。</p>
+            <h2>在线合并 MP3 等音频文件</h2>
+            <p>添加文件、排好顺序，下载一个文件即可。音频合并完全在浏览器中运行：文件在您的设备上解码、拼接和编码，因此不上传任何内容，没有大小配额，也不用排队等待。</p>
+            <h3>如何合并音频文件</h3>
+            <ol>
+                <li>把文件拖放到上方的框中，或点击选择。之后还可以用“添加更多文件”继续添加。</li>
+                <li>拖动音轨排出想要的顺序，或使用箭头调整。</li>
+                <li>可选：设置最长 3 秒的淡入淡出，让过渡更平滑。保持 0 则直接衔接。</li>
+                <li>点击“合并并下载”，将结果保存为 MP3（192 kbps）或 WAV。</li>
+            </ol>
+            <h3>可以合并哪些文件</h3>
+            <p>MP3、WAV、M4A/AAC、FLAC、OGG 和 Opus 文件可按任意顺序混合，只要浏览器能播放即可。从 WhatsApp 或 Telegram 保存的语音消息（.opus、.ogg）在支持 Opus 的浏览器中可用，例如 Chrome、Edge 和 Firefox。单声道和立体声可以混合，不同采样率的文件会自动统一。</p>
             <h3>常见用途</h3>
-            <p>合并播客的片头、正片和片尾；把多首音乐拼成一个串烧；连接分段的语音录音或有声书章节；把多个音效合成一个文件。</p>
-            <p>还需要其他处理？试试<a href="/audio-trimmer/">音频剪辑</a>、<a href="/audio-speed-changer/">音频变速</a>、<a href="/zh/volume-booster/">音量增强器</a>或<a href="/zh/converter/">音频转换器</a>。</p>
+            <ul>
+                <li>给一期播客接上片头和片尾</li>
+                <li>把几条语音消息合成一段录音</li>
+                <li>把有声书的各章合成一个文件</li>
+                <li>把多首歌曲做成串烧，中间加淡入淡出</li>
+                <li>按顺序拼接音效或铃声片段</li>
+            </ul>
+            <h3>在 iPhone 和 Android 上使用</h3>
+            <p>无需安装任何应用：在 iPhone 的 Safari 或 Android 的 Chrome 中打开本页，从手机添加文件，下载合并后的文件即可。</p>
+            <h3>限制</h3>
+            <p>合并过程中，所有音轨都保存在设备内存里。大多数电脑处理一两个小时的音频没有问题；在手机上，过长的合并可能内存不足，可以分几次合并。</p>
+            <p>想让合并后的文件更小，用<a href="/zh/audio-compressor/">音频压缩</a>；想先剪掉一部分，用<a href="/audio-trimmer/">音频剪辑</a>；需要 M4A 或 FLAC，用<a href="/zh/converter/">音频转换器</a>；某段录音比其他的小声，用<a href="/zh/volume-booster/">音量增强器</a>。</p>
         </section>
 
         <section class="faq">
             <h2>常见问题</h2>
-            <div class="faq-item"><div class="faq-q">如何在线合并音频文件？</div><div class="faq-a">添加文件，排好顺序，可选添加淡入淡出，然后点击“合并并下载”，即可得到一个合并后的文件。</div></div>
-            <div class="faq-item"><div class="faq-q">可以合并不同格式的文件吗？</div><div class="faq-a">可以。MP3、WAV、FLAC、OGG 可混合使用。浏览器会分别解码每个文件，合并结果保存为 MP3 或 WAV。</div></div>
+            <div class="faq-item"><div class="faq-q">如何把多个 MP3 合并成一个？</div><div class="faq-a">添加 MP3 文件，排好顺序，可选设置淡入淡出，然后点击“合并并下载”。您会得到一个在浏览器中生成的 MP3 或 WAV 文件。</div></div>
+            <div class="faq-item"><div class="faq-q">可以合并不同格式的文件吗？</div><div class="faq-a">可以。MP3、WAV、M4A、FLAC、OGG 和 Opus 可以在一次合并中混用。每个文件由浏览器解码，结果保存为 MP3 或 WAV。</div></div>
+            <div class="faq-item"><div class="faq-q">可以合并 WhatsApp 或 Telegram 的语音消息吗？</div><div class="faq-a">可以。从聊天中保存语音消息（.opus 或 .ogg 文件），然后添加到这里。Chrome、Edge 和 Firefox 可以播放这类文件，部分旧版 Safari 不行。</div></div>
+            <div class="faq-item"><div class="faq-q">合并会降低音质吗？</div><div class="faq-a">保存为 WAV 时，解码后的音频保持不变。保存为 MP3 时会以 192 kbps 重新编码，对语音和大多数音乐来说听起来与原文件相同。</div></div>
+            <div class="faq-item"><div class="faq-q">文件数量有限制吗？</div><div class="faq-a">没有固定限制。唯一的限制是设备内存，因为合并时所有音轨都保存在内存中。</div></div>
             <div class="faq-item"><div class="faq-q">我的音频会被上传吗？</div><div class="faq-a">不会。所有合并都通过 Web Audio API 在您的浏览器中完成。</div></div>
         </section>
     </div>