[Editor's Note: This API's documentation is no longer available. Check out the other USPS APIs in our database for similar functions.]
The U.S. Postal Service provides a suite of USPS Web Tools that customers may integrate into their own websites to validate or find mailing addresses, track and confirm mail delivery, calculate shipping rates, and create domestic or international shipping labels.
With this service, senders can create a Priority Mail Express label and an online customer record for a parcel shipped within the U.S.