Reference list of standard aviation transponder (SSR) squawk codes — the four-digit codes pilots set on their transponder, including the emergency codes every pilot memorises: 7500 hijack, 7600 lost comms, 7700 emergency.
JSON and CSV, for flight-sim tools, ATC trainers and aviation apps.
Note: many squawk codes are assigned by ATC and vary by country/region. This list covers the internationally standardised and common conspicuity codes.
Maintained by Aviation Shop — aviation gifts & pilot supplies since 2011. Try our free pilot tools & calculators (METAR decoder, weight & balance, fuel burn, crosswind, density altitude).
Corrections and additions welcome via pull request or issue.
Public domain (CC0 1.0).