What shipping services does the USPS API support?

The API supports USPS Ground Advantage, Priority Mail, Priority Mail Express for domestic shipments, and Priority Mail International, Priority Mail Express International, and Global Express Guaranteed for international shipments.

How accurate are the shipping rates?

Rates are calculated in real-time using the official USPS REST API v3 with your actual origin and destination ZIP codes. Rates include dimensional weight calculations and zone-based pricing.

Does the API support international shipping?

Yes, the API supports international shipping to over 180 countries with automatic customs form requirements (CN22/CN23) and country-specific rate calculations.

Is there a rate limit on API calls?

The default rate limit is 60 requests per minute. For higher volume needs, contact us to discuss commercial rate limits.

What happens if the USPS API is unavailable?

The API automatically falls back to cached rates when the USPS API is unavailable, ensuring your checkout process continues to work.

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Terms of Service

Last updated: March 4, 2026

By using the USPS Shipping API, you agree to be bound by these Terms of Service. If you do not agree, please do not use the service.

1. Service Description

The USPS Shipping API (“Service”) provides programmatic access to USPS shipping rate calculations for domestic and international shipments. The Service is provided by Platphorm News Network (“Provider”).

The Service integrates with the official USPS Web Tools API and may provide fallback estimated rates when the USPS API is unavailable.

2. Acceptable Use

You may use the Service for:

E-commerce shipping rate calculations
Shipping cost estimation for business applications
Integration with order management systems
Personal shipping cost research
Educational and development purposes

3. Prohibited Use

You may NOT use the Service for:

Excessive automated requests that degrade service quality
Scraping or bulk data collection
Reselling API access without authorization
Any illegal activities or fraud
Circumventing rate limits or security measures
Impersonating USPS or misrepresenting the source of rates

4. Disclaimer of Warranties

THE SERVICE IS PROVIDED “AS IS” AND “AS AVAILABLE” WITHOUT WARRANTIES OF ANY KIND, EITHER EXPRESS OR IMPLIED.

Shipping rates returned by the Service are estimates and may differ from actual USPS rates at the time of shipment. The Provider is not responsible for any discrepancies between estimated and actual shipping costs.

The Provider does not guarantee 100% uptime or uninterrupted access to the Service.

5. Limitation of Liability

IN NO EVENT SHALL THE PROVIDER BE LIABLE FOR ANY INDIRECT, INCIDENTAL, SPECIAL, CONSEQUENTIAL, OR PUNITIVE DAMAGES ARISING OUT OF OR RELATED TO YOUR USE OF THE SERVICE. THE PROVIDER'S TOTAL LIABILITY SHALL NOT EXCEED $100 USD.

6. Modifications

We reserve the right to modify these Terms at any time. Changes will be posted on this page with an updated revision date. Continued use of the Service after changes constitutes acceptance of the new Terms.

7. Governing Law

These Terms shall be governed by and construed in accordance with the laws of the Commonwealth of Virginia, United States, without regard to its conflict of law provisions.

8. Contact

For questions about these Terms, contact us at:

Email: Michael@barbineworldwide.com

Website: platphormnews.com