USPS

Setup

Real Credentials

USPS XML API calls (Verify, RateV4, etc.) — data is sent as an XML query parameter, not a request body; responses are parsed from XML to JSON.

• User ID required

Real API documentation

Input & Output Schema

Queried live from the platform. Sample values are shape-accurate placeholders (<string>, 0, an enum's first value) generated from the real schema, not invented example data.