USPS website screenshot

USPS

The United States Postal Service (USPS) provides a modern suite of RESTful APIs for address validation, domestic and international pricing, shipping label creation and cancellation, tracking, and service standards through its developer portal. The APIs replace the legacy Web Tools platform and use OAuth 2.0 Client Credentials for authentication. The platform supports both production and TEM (Testing Environment for Mailers) endpoints for developing and validating shipping integrations.

USPS publishes 5 APIs on the APIs.io network. Tagged areas include Shipping, Postal, Address Validation, Tracking, and Labels.

USPS’s developer surface includes documentation, getting-started guide, signup flow, GitHub presence, engineering blog, and 3 more developer resources.

🌐 Visit website 📡 Source on GitHub
23.2/100 emerging ▲ 8.2 Agent 16/100 agent aware Full breakdown ↓
scored 2026-07-28 · rubric v0.6
5 APIs
ShippingPostalAddress ValidationTrackingLabelsLogistics

Kin Score

Kin Score Kin Score How this is scored →
scored 2026-07-28 · rubric v0.6
Composite quality — 23.2/100 · emerging
Contract Quality 10.8 / 25
Developer Ergonomics 4.3 / 20
Commercial Clarity 0.0 / 20
Operational Transparency 0.7 / 13
Governance 0.0 / 12
Discoverability 7.4 / 10
Agent readiness — 16/100 · agent aware
Machine-Readable Contract 18 / 18
Agentic Access Contract 0 / 10
MCP Server 0 / 12
Machine-Readable Auth 0 / 10
Idempotency 0 / 9
Stable Error Semantics 0 / 8
Request/Response Examples 0 / 7
Rate-Limit Signaling 0 / 7
Typed Event Surface 0 / 6
Agent Skills 0 / 5
Well-Known Catalog 0 / 4
Consent & Bot Identity 0 / 3
A2A Agent Card 0 / 8
Dry-Run / Simulate Mode 0 / 4
Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. This rating is computed from github.com/api-evangelist/usps: open an issue to ask a question, or submit a pull request to add artifacts. Want it done for you? Prioritized profiling — $2,500 →

APIs 5

Individual APIs this provider publishes, each with its own machine-readable definition.

USPS OAuth 2.0

Token endpoint for OAuth 2.0 Client Credentials authentication used to authorize requests to all USPS API products.

USPS Addresses API

Verify and standardize US addresses to USPS specifications, reducing shipping delays and errors.

USPS Tracking API

Retrieve tracking status and delivery events for shipped packages across USPS services.

USPS Labels API

Create and cancel domestic shipping labels with integrated address standardization, pricing, and manifesting.

USPS Domestic Prices API

Retrieve current pricing information for USPS domestic shipping products and services.

GraphQL 1

GraphQL schemas published by this provider.

USPS GraphQL Schema

Conceptual GraphQL schema for the United States Postal Service (USPS) APIs. This schema models the capabilities exposed by the USPS REST API developer portal at [https://develop...

GRAPHQL

Security Posture 1

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Usps Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Resources

Get Started 2

Portal, sign-up, and the first successful call

GettingStarted
GettingStarted
 Signup
Signup

Documentation 1

Reference material describing how the API behaves

Documentation
Documentation

Build 1

SDKs, sample code, and the tooling you integrate with

GitHub
GitHub

Access & Security 1

Authentication, authorization, and security posture

DomainSecurity
DomainSecurity

Company 3

The organization behind the API

LinkedIn
LinkedIn
 Website
Website
 Blog
Blog

Source (apis.yml)

apis.yml Raw ↑ 
aid: usps
name: USPS
description: The United States Postal Service (USPS) provides a modern suite of RESTful APIs for address validation, domestic
  and international pricing, shipping label creation and cancellation, tracking, and service standards through its developer
  portal. The APIs replace the legacy Web Tools platform and use OAuth 2.0 Client Credentials for authentication. The platform
  supports both production and TEM (Testing Environment for Mailers) endpoints for developing and validating shipping integrations.
type: Index
accessModel:
  pricing: unknown
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Unknown
  confidence: low
  source: []
  generated: '2026-07-22'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/usps.png
tags:
- Shipping
- Postal
- Address Validation
- Tracking
- Labels
- Logistics
url: https://raw.githubusercontent.com/api-evangelist/usps/refs/heads/main/apis.yml
created: '2026-05-11'
modified: '2026-05-11'
specificationVersion: '0.19'
apis:
- aid: usps:oauth2
  name: USPS OAuth 2.0
  description: Token endpoint for OAuth 2.0 Client Credentials authentication used to authorize requests to all USPS API products.
  humanURL: https://developers.usps.com/Oauth
  baseURL: https://apis.usps.com/oauth2/v3
  tags:
  - OAuth
  - Authentication
  properties:
  - type: Documentation
    url: https://developers.usps.com/Oauth
  - url: graphql/usps-graphql.md
    type: GraphQL
- aid: usps:addresses
  name: USPS Addresses API
  description: Verify and standardize US addresses to USPS specifications, reducing shipping delays and errors.
  humanURL: https://developers.usps.com/addressesv3
  baseURL: https://apis.usps.com/addresses/v3
  tags:
  - Address Validation
  properties:
  - type: Documentation
    url: https://developers.usps.com/addressesv3
- aid: usps:tracking
  name: USPS Tracking API
  description: Retrieve tracking status and delivery events for shipped packages across USPS services.
  humanURL: https://developers.usps.com/trackingv3
  baseURL: https://apis.usps.com/tracking/v3
  tags:
  - Tracking
  - Shipping
  properties:
  - type: Documentation
    url: https://developers.usps.com/trackingv3
- aid: usps:labels
  name: USPS Labels API
  description: Create and cancel domestic shipping labels with integrated address standardization, pricing, and manifesting.
  humanURL: https://developers.usps.com/labelsv3
  baseURL: https://apis.usps.com/labels/v3
  tags:
  - Labels
  - Shipping
  properties:
  - type: Documentation
    url: https://developers.usps.com/labelsv3
- aid: usps:prices
  name: USPS Domestic Prices API
  description: Retrieve current pricing information for USPS domestic shipping products and services.
  humanURL: https://developers.usps.com/pricesv3
  baseURL: https://apis.usps.com/prices/v3
  tags:
  - Pricing
  - Shipping
  properties:
  - type: Documentation
    url: https://developers.usps.com/pricesv3
common:
- type: DomainSecurity
  url: security/usps-domain-security.yml
- type: LinkedIn
  url: https://www.linkedin.com/company/usps
- type: Website
  url: https://www.usps.com
- type: Documentation
  url: https://developers.usps.com
- type: GettingStarted
  url: https://developers.usps.com/getting-started
- type: Signup
  url: https://developers.usps.com/apis
- type: GitHub
  url: https://github.com/USPS/api-examples
- url: https://about.usps.com/news/latestnews.rss
  type: Blog
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com