Production USPS v3 REST API for developers. Address validation, package tracking, rate shopping, label creation, and service standards — all through a single, modern JSON API.
- Direct USPS v3 access — No middlemen, no per-label fees. Flat monthly pricing.
- BYOK (Bring Your Own Keys) — Use your own USPS credentials. No vendor lock-in.
- SDKs for every stack — Python, Node.js, PHP. Drop-in packages on PyPI, npm, and Packagist.
- USPS-approved — Registered application (REVASSEROSSHIP). 293 tests. 41 API routes.
- Rate limit handling — Built-in token management and retry logic so you don't have to.
| Language | Package | Install |
|---|---|---|
| Python | usps-v3 |
pip install usps-v3 |
| Node.js | usps-v3 |
npm install usps-v3 |
| PHP | revaddress/usps-v3-php |
composer require revaddress/usps-v3-php |