USPS WCF Web Application Programming Interface.
To learn more about the USPS Web Tools API, visit
Select USPS Web Tool to use:
Never get another address or Zip Code™ wrong again with our address standardization city and state lookup APIs.
Tracking & Delivery Information
Get estimated delivery information and track packages until they arrive with Tracking & Delivery Information APIs.
Calculate postage rates quickly and easily online for domestic and international shipping.
Print Shipping Labels
Print a complete shipping label with a tracking barcode to track packages seamlessly with one of our PC Postage® partners.
Stop going to the Post Office™ to drop off your packages. With the Package Pickup API, you can submit a pickup request and we will pick up your packages for free.
Service Standards & Commitments
Get estimates on delivery and receive guaranteed Commitments with certain services.