IATA to ICAO Airport Code Converter

About this calculator

Airports are identified by two different code systems that serve different audiences. The 3-letter IATA code (like JFK or LHR) is what you see on boarding passes, luggage tags and airline booking systems, assigned by the International Air Transport Association. The 4-letter ICAO code (like KJFK or EGLL) is used by pilots, air traffic control and flight planning software, assigned by the International Civil Aviation Organization — it often just adds a country/region prefix letter to the IATA code, but not always.

This converter looks up the matching code in either direction for major international airports, which is useful for pilots, dispatchers, aviation enthusiasts, and developers building flight-tracking or booking tools that need to bridge passenger-facing IATA data with operational ICAO data.