IATA Airport Code Validator

IATA airport codes: the 3-letter passport of every commercial flight

An IATA airport code is a three-letter uppercase identifier (A-Z, no digits, no diacritics) assigned by the International Air Transport Association under IATA Resolution 763. The directory currently lists roughly 13 000 airport entries, but only about 4 000 of those are active commercial passenger fields — the rest are cargo hubs, military bases that accept civilian charter, seaplane bases, helipads with scheduled service and a long tail of historic codes that were retired but kept on file to prevent collision.

A correct validator does not just check shape (/^[A-Z]{3}$/); it also confirms the code is assigned to a real, currently operating airport. XYZ matches the pattern but has never been issued. STI looks like Santiago but is actually Cibao International in the Dominican Republic — the city of Santiago (Chile) uses SCL. This is why airport validators ship with a lookup table sourced from OpenFlights, OurAirports or a paid IATA Codes Directory feed.

Top Brazilian airports by passenger traffic

Brazil has roughly 26 airports with both IATA and ICAO codes serving regular commercial flights, plus dozens of regional fields with ICAO-only codes. The high-volume terminals:

• GRU São Paulo / Guarulhos — ~43 M passengers/year, Brazil's primary hub, operated by GRU Airport (concessionaire)
• GIG Rio de Janeiro / Galeão — international gateway for Rio
• BSB Brasília / Presidente Juscelino Kubitschek — federal capital hub, geographic center of the country
• CGH São Paulo / Congonhas — downtown SP, short-haul domestic only, slot-restricted
• SDU Rio de Janeiro / Santos Dumont — downtown Rio, mostly the GRU/CGH shuttle
• CWB Curitiba / Afonso Pena, POA Porto Alegre / Salgado Filho, FOR Fortaleza / Pinto Martins
• REC Recife / Guararapes, NAT Natal / São Gonçalo do Amarante, BEL Belém / Val de Cans, SSA Salvador / Deputado Luís Eduardo Magalhães
• MAO Manaus / Eduardo Gomes, CNF Belo Horizonte / Confins, VCP Campinas / Viracopos (Azul's main hub)

Top global airports and the codes you'll see on screens

In passenger volume the heavyweights are ATL Hartsfield-Jackson Atlanta (the world's busiest most years), DXB Dubai International, PEK Beijing Capital, HND Tokyo Haneda, LAX Los Angeles, ORD Chicago O'Hare, LHR London Heathrow, CDG Paris Charles de Gaulle, FRA Frankfurt, HKG Hong Kong, AMS Amsterdam Schiphol, CGK Jakarta Soekarno-Hatta, ICN Seoul Incheon. For US travelers the four New York-area fields are JFK, LGA, EWR Newark and HPN White Plains — note that EWR is physically in New Jersey but billed by airlines as a New York airport.

Airport vs city codes: the trap that breaks bookings

When a metropolis has more than one commercial field IATA assigns a separate metropolitan area code that groups them all. The classic three to memorize:

• NYC = New York City area: JFK + LGA + EWR
• LON = London area: LHR + LGW Gatwick + STN Stansted + LCY City + LTN Luton + SEN Southend
• SAO = São Paulo: GRU + CGH + VCP; RIO = GIG + SDU

City codes are accepted by booking engines for fare searches but rejected on boarding passes and bag tags, which require a specific airport. A validator that flags SAO as invalid for an airport field is doing its job; flagging it as invalid for a fare search is a false positive.

ANAC categorization in Brazil (TPS classes)

Brazil's civil aviation regulator ANAC ranks Terminal de Passageiros (TPS) facilities by yearly throughput: Class IV (over 8 M pax/year — GRU, GIG, BSB, CGH, SDU), Class III (1.5–8 M — most state capitals), Class II (500 k–1.5 M), Class I (under 500 k). Class is published in ANAC anuário data and changes when traffic crosses a threshold — useful when ranking which IATA codes are "major" in a Brazilian context.

Codeshare flights and IATA reality

A single physical departure can show up under many different flight numbers — one for each codeshare partner. A LATAM LA8084 from GRU might also be sold as Iberia IB7350, Qantas QF3535 and American AA6190. All four numbers reference the same aircraft, same gate, same crew, same IATA airport codes. Validators consuming flight data must dedupe by operating carrier, not marketing carrier, or they will overstate seat supply.

Open data sources for IATA airport lookups

• OpenFlights airports.dat (~7 700 entries, CC-BY-SA): the most-used open airport table for hobby projects.
• OurAirports.com: ~80 000 records including small grass strips and helipads; IATA field is sparse but quality is excellent.
• FlightAware Aero API, OAG, Cirium: paid commercial feeds with daily delta updates.
• IATA Codes Directory at iata.org/codes: official source, paid subscription, used by GDSes and TMCs.

When IATA codes change or get retired

Codes can change when a new replacement airport opens. MEX stays put but Mexico City built NLU Felipe Ángeles as a relief field; Istanbul shifted long-haul from SAW Sabiha Gökçen and ISL (Atatürk, now closed to civil) to IST (the new Istanbul Airport opened in 2018, inheriting the old code). Berlin Tegel TXL was retired when BER opened. Caching a 2017 IATA table guarantees stale data for at least a dozen high-traffic markets — refresh quarterly.

FAQ

Are 3 uppercase letters always enough to validate an IATA airport code? Shape-wise yes, semantically no — only ~4 000 of the 17 576 possible three-letter combinations are issued. A real validator pairs the regex with a lookup table.

Where do I find a free, current list of IATA airport codes? OpenFlights and OurAirports are the standard open datasets. Refresh them quarterly to catch new openings, closures and rebrandings.

Why does NYC not work as an airport code on my boarding pass? NYC is a metropolitan area code, not an airport. Boarding pass origin/destination fields require JFK, LGA or EWR.

Can the same IATA code refer to two different airports? Not concurrently. IATA enforces uniqueness across all currently active airports. Retired codes can be reissued years later, which is why historic flight data parsers need a date-aware lookup.

What about heliports and seaplane bases? Most have ICAO codes but no IATA code unless they offer scheduled commercial service. JRA West 30th St. Heliport (NYC) is a famous exception.