AWB number validator
Paste an air waybill number to check its mod-7 check digit and see which airline issued it. It runs instantly, needs no account, and catches most typos before you chase a shipment that "doesn't exist".
How the AWB check digit works
An airline air waybill number has 11 digits, usually written XXX-XXXXXXXX. The first three digits are the airline prefix. The next seven are a running serial number, and the final digit is a check digit: the remainder when those seven digits are divided by 7. The prefix is not part of the calculation.
Take 235-94456121. The serial body is 9445612. Dividing by 7 gives 1,349,373 with a remainder of 1, and the number ends in 1 — so it is valid. Change any one of the first seven digits by anything other than 7 and the remainder changes, which is why the check catches the most common single-key typos.
What a pass does — and does not — mean. A valid check digit proves the number is well-formed, not that the shipment exists or has been booked. Substitutions that differ by exactly 7 (0↔7, 1↔8, 2↔9) and many transposed digits slip through. If a valid number returns no tracking data, see troubleshooting.
House AWBs are different
Freight forwarders issue House AWB numbers in their own formats — often letters plus digits — and they do not follow the airline mod-7 rule. If your number fails here and contains letters or has the wrong length, it is probably a House AWB. Ask your forwarder for the Master AWB, which is the number the airline tracks. Our guide to Master vs House AWBs explains why.
Common reasons a number fails
- Spreadsheet damage: Excel drops leading zeros, so 020-12345675 becomes 2012345675 (10 digits).
- Transcription from a photo or fax: 1/7, 3/8 and 5/6 are easy to misread.
- Copying the wrong box: booking references, flight numbers and House AWBs often sit near the AWB on paperwork.
- Missing a digit: the serial must be exactly 8 digits including the check digit.
For a deeper explanation with more worked examples, read AWB number format and the mod-7 check digit.