USPS Domestic Prices API
Provides postage pricing for domestic USPS shipments based on origin and destination ZIP Codes, weight, dimensions, and mail class. Supports base rate lookups, extra service rates (insurance, signature confirmation, etc.), and total rate calculations.
Documentation
Specifications
OpenAPI
https://raw.githubusercontent.com/api-evangelist/united-states-postal-service/refs/heads/main/openapi/united-states-postal-service-domestic-prices-openapi.yml
JSON-LD
https://raw.githubusercontent.com/api-evangelist/united-states-postal-service/refs/heads/main/json-ld/united-states-postal-service-domestic-context.jsonld