One-click custom domains for SaaS. Automatic DNS, domain verification, and SSL/TLS on your users' own domains.

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CustomDomain™ lets a platform's users connect a domain they already own in one click. It detects the user's DNS provider, writes the records automatically, verifies them against public DNS, and issues and renews TLS certificates at a managed edge. 178 DNS and registrar providers are catalogued: 62 configure automatically (55 by scoped API token, 6 by provider OAuth, 1 by Domain Connect), and the other 116 use a guided manual flow with automatic verification. A domain connected through provider authorization is typically live with HTTPS in about 30 seconds.

The connect flow, run on a real domain: provider detected, records written and verified, certificate issued.

Your user types their domain

Live with HTTPS, seconds later

Also: e-commerce platforms (a storefront per merchant domain), creator tools (a domain per creator), and any multi-tenant SaaS where tenants deserve their own name in the address bar. Start at custom domains for SaaS.

One connect flow across the entire provider landscape: one-click authorization where providers support it, API tokens where they offer them, and a guided manual path with automatic verification everywhere else. No user ever hits a dead end.

MCP server: https://mcp.customdomain.ai/mcp (streamable HTTP), the official CustomDomain™ server, listed in the MCP registry as ai.customdomain/mcp, server version 0.6.0 with 20 tools. Setup for Claude, Cursor, VS Code and GitHub Copilot: customdomain-mcp.

claude mcp add --transport http customdomain https://mcp.customdomain.ai/mcp \
  --header "Authorization: Bearer $CUSTOMDOMAIN_API_KEY"

{
  "mcpServers": {
    "customdomain": {
      "type": "http",
      "url": "https://mcp.customdomain.ai/mcp",
      "headers": { "Authorization": "Bearer cd_live_YOUR_KEY" }
    }
  }
}

# 1. Create a connection for your user's domain (the application comes from the key)
curl -X POST https://api.customdomain.ai/v1/connections \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"domain": "app.customer.com"}'

# 2. Start one-click provider authorization (fallbacks: token or guided manual).
#    return_origin is required and must be on your allowlist.
curl -X POST https://api.customdomain.ai/v1/connections/<ID>/oauth:start \
  -H "Authorization: Bearer $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"return_origin": "https://app.yourplatform.com"}'

# 3. Poll until live: records written, verified in public DNS, TLS issued
curl https://api.customdomain.ai/v1/connections/<ID> \
  -H "Authorization: Bearer $API_KEY"

How do I let my users connect their own domain? Embed the connect widget or call the REST API. CustomDomain™ handles provider detection, DNS, verification, certificates, and serving.

What is bring your own domain (BYOD)? Letting each customer run your product on a domain they own, like app.acme.com, instead of a shared subdomain. Full definition, and custom domain vs subdomain if you're weighing the tradeoffs.

How fast can a customer domain go live? With one-click provider authorization, about 30 seconds from typing the domain to serving HTTPS. Guided manual setups depend on the customer applying records; verification is detected automatically once they do.

Does this work for email domains? Yes. SPF, DKIM, DMARC, MX, and return-path records are written through the same connect flow. See connect-domain-for-email-platforms.

Is there a free trial? Yes. Every self-serve plan starts with a 14 day free trial, from $10 a month (Starter, 10 domain connections a year), and a new workspace connects its first ten domains without a card. Every plan includes the Connect DNS engine, the widget and SDK, the REST API and webhooks, DNS drift detection, and the MCP server. The reverse-proxy edge and the SSL management API start on the Growth plan. See pricing.

custom-domain-checks runs DNS and SSL health checks on the custom domain of a GitHub Pages site: DNS resolution, CNAME or apex target correctness, domain verification (takeover protection), CAA compatibility, certificate expiry, and HTTPS enforcement. Add it to a workflow as a GitHub Action today and it annotates every problem and fails the job on one. The GitHub App version posts a Domain health check on every push and opens a tracking issue when something breaks; its service is deployed, but the App is not registered on GitHub yet, so it cannot be installed from GitHub today. The source is open and free to run yourself.

Connect your first domain free →

_{Docs: docs.customdomain.ai · Questions: Discussions · Status: status.customdomain.ai · Account and billing: connect@customdomain.ai · Security: security@customdomain.ai (policy) · Security posture and sub-processors: trust.customdomain.ai · Book a call}

_{CustomDomain™ is a product of EverJust Company.}