Trace

Carrier tracking

USPS tracking API

USPS (United States Postal Service) delivers to every US address and is the default carrier for most domestic e-commerce. Store builders and marketplaces need USPS tracking to power order-status pages and delivery notifications.

Trace accepts USPS tracking numbers and normalizes USPS scan events into a consistent timeline, so your application can show the same status vocabulary across USPS, UPS, FedEx, and every other carrier.

Carrier type

domestic

Regions

US

Carrier code

usps

Track USPS in one request

USPS tracking numbers are 20-22 digits and usually start with 9. Trace detects common USPS formats automatically. Send a tracking number to the Trace API and receive a normalized event timeline.

curl -X POST https://api.traceapi.dev/v1/track \
  -H "Authorization: Bearer trc_test_key" \
  -H "Content-Type: application/json" \
  -d '{"tracking_number":"YOUR_TRACKING_NUMBER"}'

USPS tracking FAQ

Does Trace support USPS tracking?

Yes. Trace accepts the usps carrier code and returns a normalized event timeline for USPS shipments when a source provides usable data.

How do I track USPS packages with Trace?

Send a POST request to /v1/track with the tracking number and, for ambiguous formats, the carrier code usps. Trace returns normalized statuses and dated events with timestamps and locations.

Is USPS detected automatically?

USPS tracking numbers are 20-22 digits and usually start with 9. Trace detects common USPS formats automatically.

Start tracking USPS for free.

Create an account, generate an API key, and track your first USPS package in under two minutes.

Get your free API keyAll carriers