Tracking number identifier
Which carrier does this number belong to, and was it typed correctly? Checked offline, from the number's pattern and check digit alone.
Format check · offline
RB123456785GB
A postal service (UPU S10) · International postal item number
Check digit OK
Ends in GB: posted in United Kingdom. Starts with RB, the service indicator.
1Z999AA10123456784
UPS · 1Z tracking number
Check digit OK
Shipper account 999AA1, service code 01.
9400111201080805483017
USPS · Intelligent Mail package barcode (IMpb)
Check digit wrong: expected 6, found 7
A format match only means the number is well formed. It doesn't prove that a parcel exists or where it is, and nothing was sent to any carrier.
What it checks
Carriers number parcels in their own patterns, and most add a check digit: a last digit worked out from the others, so that a mistyped number can be spotted. The identifier matches each number against known patterns and recalculates the check digit. It never contacts a carrier, so it can't tell you whether a parcel exists or where it is.
- International post (UPU S10, used by Royal Mail, USPS and many other posts): two letters, eight digits, a check digit and the country code, as in RB123456785GB.
- UPS: 18 characters starting 1Z.
- USPS: 22 or 26 digits starting 92 to 95, sometimes after a 420 + ZIP routing code.
- FedEx: 12 or 15 digits, or 22 digits starting 96. DHL Express: 10-digit waybill numbers.
Sources
- Universal Postal Union, UPU standards: S10, the 13-character identifier for postal items and its check digit.
- USPS, Publication 199: Intelligent Mail package barcode (IMpb) formats.
- Jeff Keen and contributors, tracking_number_data (MIT licence): documented patterns, check-digit methods and test numbers for UPS, FedEx, USPS, DHL and others, used to verify this tool.
Questions
The check digit is right. Does that mean my parcel is real?
No. It only means the number is well formed. Anyone can make up a number that passes; only the carrier knows whether a parcel exists.
Why can a number match more than one format?
Some patterns overlap, such as all-digit numbers of the same length. The best match is shown first; the carrier named on your order confirmation settles it.
Where do I track the parcel?
On the carrier's own website or app. Reach it by typing its address yourself rather than by following a link in a message.