What carrier is this tracking number?
Paste a tracking number and we'll match it against the carrier formats we know — including full decoding of international postal numbers. Then track it for real across 3,000+ carriers.
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How detection works
A tracking number is not random. It is a barcode payload with a structure the carrier chose, and that structure often gives the carrier away. Detection here is pattern matching: the number is stripped of spaces and punctuation, uppercased, and tested against every format in our table. Each match carries a specificity score, and the list is ranked by it.
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Paste the number
Spaces, hyphens and dots are stripped automatically, and lowercase letters are uppercased. Nothing leaves your browser — the matching runs on your device.
- 2
Read the ranked candidates
Distinctive formats resolve to one carrier. Plain numeric formats are shared, so you get every carrier that uses the shape, most distinctive first.
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Track it to confirm
Format matching is a hint, not proof. The Track button checks the number against the live carrier networks, which is the only authoritative answer.
The honest limitation is worth stating plainly, because most tools like this one hide it. A prefix such as 1Z or TBA is effectively unique, and the S10 postal format is unmistakable. A bare string of twelve digits is not — several carriers use it, and no amount of analysis of those digits will tell you which. In that case the format tells you what the number could be, and only a live query against the carrier networks tells you what it is.
Tracking number formats by carrier
A starter set of the formats that are distinctive enough to be worth matching. Carriers add and retire number ranges regularly, so treat this as a working reference rather than a specification.
| Carrier | Format | Example | Confidence |
|---|---|---|---|
| UPS | 1Z + 16 letters/digits (18 total) | 1Z999AA10123456784 | High |
| UPS Mail Innovations | MI + 6-digit mailer id + package id | MI000000271234567890 | High |
| USPS | 22, 26 or 30 digits starting 92, 93, 94 or 95 | 9400111899223197428490 | High |
| USPS | 16 digits starting 70, 03, 23, 14 or 77 | 7000123456789012 | Medium |
| FedEx | 12 digits | 999999999999 | Low — shared format |
| FedEx (Ground / SmartPost) | 15 digits | 999999999999999 | Low — shared format |
| FedEx (Ground 96 / SmartPost) | 20 or 22 digits, often starting 96 | 9612019987654312345671 | Medium |
| DHL Express | 10 digits | 1234567890 | Low — shared format |
| DHL eCommerce | 2 letters + 9–22 digits | GM123456789012345 | Medium |
| Postal operator (UPU S10) | 2 letters + 9 digits + 2-letter country code (13 total) | EE123456785US | High |
| OnTrac | C or D + 14 digits | D10000000000000 | High |
| SF Express | SF + 12–15 digits | SF1234567890123 | High |
| Cainiao / AliExpress Standard | LP + 14–18 digits | LP00612345678901 | High |
| Yanwen | UV or LY + 9 digits + CN | UV123456789CN | High |
| YunExpress | YT + 16 digits | YT1234567890123456 | High |
| 4PX | 4PX + 14–18 digits | 4PX3000123456789 | High |
| GLS | 11 digits | 12345678901 | Low — shared format |
| DPD | 14 digits | 01234567890123 | Low — shared format |
| TNT | GE or CJ + 9 digits + 2 letters | GE123456789WW | High |
| Aramex | 8 or 11 digits | 12345678901 | Low — shared format |
| Amazon Logistics | TBA + 9–12 digits | TBA123456789012 | High |
| Purolator | 3 letters + 9 digits | ABC123456789 | Medium |
| LaserShip / OnTrac | 1LS + 12–16 digits | 1LS724000000000 | High |
Confidence reflects how uniquely the shape identifies one carrier, not how reliable the carrier is. Reviewed quarterly against our live carrier directory.
UPU S10 explained
Any parcel that crosses a border through the postal system — rather than through a courier — carries a number issued under UPU standard S10. It is the most decodable format in shipping, because the standard fixes what each part means:
- Characters 1–2: the service.The first letter is the service indicator; the second is the issuing operator's own sub-code and means nothing outside that operator.
- Characters 3–10: the serial.Eight digits, unique within the issuing operator's number range.
- Character 11: the check digit. Computed from the serial, so a mistyped number can be caught without querying anyone.
- Characters 12–13: the origin country. The ISO 3166 alpha-2 code of the postal operator that issued the number — where it started, never where it is going.
| First letter | Service |
|---|---|
| A | Letter post, other service |
| C | Parcel post |
| E | EMS / express |
| L | Tracked letter, no signature required |
| M | M bag — a direct sack of printed matter |
| R | Registered mail, signature on delivery |
| U | Other tracked item |
| V | Insured letter or parcel |
| Z | Reserved / operator-specific |
Per UPU standard S10. Operators occasionally use letters outside this set for domestic products that never leave their network.
The check digit, in full
Multiply the eight serial digits by the fixed weights 8, 6, 4, 2, 3, 5, 9, 7 and sum the products. Take the remainder modulo 11. If the remainder is 1 the check digit is 0; if it is 0 the check digit is 5; otherwise it is 11 minus the remainder. The two special cases exist because 10 and 11 are not single digits.
Worked examples
Example 1 — 1Z999AA10123456784
Eighteen characters beginning 1Z. No other carrier uses that prefix, so this resolves to UPS with high confidence without any further analysis. The six characters after 1Z are the shipper's account number, which is why parcels from the same seller share a long common prefix.
Example 2 — EE123456785US
Two letters, nine digits, two letters: an S10 postal number. Decoded:
E → EMS / express service
serial 12345678, check digit 5
8×1 + 6×2 + 4×3 + 2×4 + 3×5 + 5×6 + 9×7 + 7×8 = 204
204 mod 11 = 6 → check digit = 11 − 6 = 5 ✓
US → issued by the United States Postal Service
An EMS item posted in the United States. The destination is not encoded anywhere in the number.
Example 3 — RR123456785CN
Same serial, same valid check digit, different service and origin: Rfor registered mail with signature on delivery, issued in China. Numbers like this usually travel by China Post and are handed to the destination country's postal operator for the final leg — which is why tracking often appears to stop at the border and resume days later under a different carrier's scans.
If the number won't resolve
Three situations account for nearly every unresolvable number, and each has a different fix:
- It is an order number, not a tracking number. Marketplace order references are often the same length and get copied by mistake. If it contains a dash and letters in the middle, check the seller's email again.
- The label exists but nothing has been scanned. A number is issued when a label is bought, which can be days before the parcel is handed over. There is genuinely nothing to find yet.
- You are asking the wrong carrier.The most common cause of “not found” by a distance. Cross-border parcels change hands, and the number that works on the destination operator's site may be a different number entirely. Our status decoder covers what the resulting messages mean.
How we source and maintain this data
The pattern table is built from carrier documentation, the UPU S10 standard, the open-source tracking-number-data catalogue, and the carrier detection our own tracker already runs. Because the tracker sees real numbers resolve against real carriers every day, patterns that stop working show up here rather than quietly rotting.
We deliberately do not include every carrier we can track. Adding a pattern that matches any 9-digit number would technically raise coverage while making every result meaningless, so a format only earns a row if it is distinctive enough to be worth showing.
Review cadence: Format patterns are reviewed quarterly and whenever our carrier directory picks up a new number range. Last reviewed August 2026. This tool is built and maintained by the ParcelTracking team, who run multi-carrier tracking across 3,000+ carriers.
Primary sources
Tracking number format FAQ
Often, yes. Some formats are unmistakable: UPS numbers start with 1Z, Amazon Logistics uses TBA, and any 13-character number shaped as two letters, nine digits and a two-letter country code is a postal item under the UPU's S10 standard. But plenty of carriers use plain 10, 11, 12 or 14-digit numbers with nothing distinguishing about them, and in those cases the format narrows the field without identifying the carrier. That is why this tool shows a ranked list rather than a single confident answer.
S10 is the Universal Postal Union standard that lets postal operators in different countries track the same item. The format is two letters, nine digits and two more letters — for example RR123456785CN. The first letter is the service type, the digits are a serial number ending in a check digit, and the final two letters are the ISO country code of the operator that issued the number.
The first letter is the service indicator: R is registered mail, E is EMS or express, L is a tracked letter with no signature, C is a parcel, V is insured and M is an M bag of printed matter. The second letter is assigned by the issuing postal operator and carries no standard meaning — any tool claiming to decode it is guessing.
They are the ISO 3166 country code of the postal operator that issued the number, which is the origin — not the destination. A number ending CN was issued by China Post, whether it is heading to Berlin or Boston.
Yes, and you probably should. Thousands of regional couriers and e-commerce carriers use plain numeric formats we deliberately do not guess at. Paste the number into our tracker and it will query the live carrier networks and auto-detect across 3,000+ carriers, which resolves cases that no format table can.
Almost certainly not. A failed check digit on an S10 number nearly always means a typo, most often two transposed digits, when someone has retyped the number from a label or a screenshot. Re-read it from the original source. It is only worth suspecting a fabricated number if it was supplied by a seller who has gone quiet and it has never produced a single carrier scan.
Because they genuinely share the format. A bare 12-digit number is used by FedEx and by several regional carriers; 10 digits could be DHL Express or another operator entirely. Knowing the origin country, or which shop you ordered from, narrows it far faster than the digits ever will — and the live lookup settles it.
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