Whose tracking number is this?
Some shipping confirmations never actually say which company is delivering the package — just a string of letters and numbers. Paste that string below and this tool matches its shape against known formats from eight major couriers to tell you who most likely issued it.
A tracking number is a fingerprint before it’s a lookup key
Retailers and marketplaces rarely name the courier outright in a shipping email — you just get a code. But that code isn’t random. Every courier builds its tracking numbers around a consistent shape: a set length, a recognizable prefix, sometimes a mix of letters and digits in a specific order. Once you know what to look for, the number itself tells you who’s actually holding the package, well before you ever load a tracking page.
That matters most for cross-border and marketplace orders — Shein, Temu, AliExpress, and similar platforms route packages through a rotating cast of regional couriers, and the tracking number is often the only clue you get about which one picked up your specific order.
Couriers this tool recognizes
Eight major couriers this tool can detect by tracking number format, plus AliExpress included for context since it’s a common source of confusion.
1234567890
Express numbers are typically 10 numeric digits. eCommerce and Parcel shipments vary more, often with a GM, JJD, or JVGL prefix.
SPX123456789012345
Begins with SPX or SX, followed by 13 to 16 digits. SpeedX is SHEIN’s primary US last-mile partner.
C11081500011234
Commonly starts with C1, D1, or similar two-character codes followed by a run of digits, used across OnTrac’s West Coast and former LaserShip territory.
UUS6181780830420
Almost always starts with UUS or UNIA, followed by 13 to 19 digits. A frequent last-mile partner for Shein and Temu.
TBA305477112000
Starts with TBA (US), TBC (Canada), or TBM (Mexico), followed by 12 digits. Trackable only through an Amazon account, not third-party sites.
781234567890
Numeric only, no letter prefix. Length signals the service: 12 digits for most Express and Ground, up to 22 for Freight.
1LS0123456789
Older LaserShip numbers often start with 1LS. LaserShip has merged into OnTrac, so both formats route through the same current network.
LP00123456789012
Most often starts with LP followed by 10 to 18 digits. Alibaba’s logistics arm, commonly seen on AliExpress orders.
Not a courier format
AliExpress is a marketplace, not a shipping company — it doesn’t issue its own tracking numbers. Orders are handed to a courier like Cainiao, UniUni, or SpeedX, and that courier’s format is what actually shows up on your tracking number.
The matching logic behind the scan
Strip formatting
Spaces, dashes, and other punctuation are removed first, since retailers often add these purely for readability and they aren’t part of the actual identifier.
Check for a known prefix
Many couriers lead with a distinct letter combination — TBA, SPX, UUS, LP, and similar. A prefix match is the strongest signal this tool uses.
Fall back to length and character pattern
Couriers like FedEx use no letter prefix at all, so numeric-only formats are distinguished by their digit count instead.
Flag confidence level
A distinct prefix match is marked high confidence. A length-only match, which can occasionally overlap between couriers, is marked as a more moderate confidence result.
Where format-matching can’t help
- Some couriers occasionally reuse a similar format to another, especially smaller regional last-mile carriers — a match should be treated as a strong lead, not a certainty.
- A single package can carry more than one tracking number across its journey. An international order might start under one courier’s number for the overseas leg, then switch to a completely different number once a local courier takes over for final delivery.
- Retailer order numbers and internal reference codes are sometimes mistaken for tracking numbers. If a result seems off, double check that the string you entered came from a field actually labeled “tracking number,” not an order ID.
- Formats do shift over time as couriers change systems, so a pattern that was reliable a year ago can occasionally stop applying to new shipments.