ICAO address lookup
Paste a 24-bit aircraft address and get the tail number and country. In many countries the tail number is encoded in the address as arithmetic. Other countries require a database lookup.
One or a whole list, in either direction. Any separator works.
Or click an example
Paste an address above, or try one of the examples. The message decoder will give you an address out of a raw message.
How this works
- Where the tail number is in the address
- The FAA does not pick an address and write it down next to a tail number. It counts. Addresses A00001 through ADF7C7 run one for one against N1 through N99999, so an address and a tail number are the same fact written two ways. Change the tail number and the address changes with it. Canada, Japan, South Korea, France, Germany and about a dozen more countries use the same kind of arithmetic with their own ranges.
The US block starts at address A00001.
Base = 0xA00001The first digit after N picks a stride of 101,711 addresses. N1 starts at offset 0.
(1 − 1) × 101,7110Each further digit skips 601 letter-suffix codes and picks the next stride.
601 + 2 × 10,111+ 20,823Third digit.
601 + 3 × 951+ 3,454Fourth digit.
601 + 4 × 35+ 741A fifth digit sits after the 25 letter-suffix slots.
25 + 5+ 30The total offset from the base is 25,048.
0xA00001 + 25,048= 0xA061D9- Registered addresses
- Most countries hand out addresses from a register. The number says nothing about the marks painted on the tail, and there is no arithmetic to run. A register lookup is a weaker answer than a computation: the database is only right until somebody re-registers the aircraft, which can happen while the address stays the same.
- What an address identifies
- The 24 bits belong to the airframe, not to the flight. One aircraft broadcasts the same address on every trip it makes, which is how a receiver can follow it through a whole day. Re-register the aircraft and the marks change. In most of the world the address does not.
Know the tail number already?
Paste a tail number and get the hex address. ADS-B software and history sites index on the address, not the registration.
Open the tail number to hex converterGot a raw message instead?
The address is 24 of the 112 bits in a broadcast. Paste the full message to see the address, altitude, position, speed and every other field.
Open the ADS-B message decoderWe turn millions of these into prints
One address through a day is a flight path. The airport prints layer millions of them into a single image, colored by altitude.
See the airport prints