ShipEngine

ShipEngine is a shipping API platform that enables ecommerce businesses, marketplaces, and logistics applications to connect with a global network of shipping carriers through a single integration. Rather than building individual integrations with UPS, FedEx, USPS, DHL, and dozens of regional carriers, developers use the ShipEngine API to access rate comparison, label generation, tracking, and address validation across all carriers simultaneously. The platform processes over a billion shipments annually and is used by major ecommerce platforms and shipping solutions as their underlying carrier connectivity layer. Rate shopping compares prices and transit times across carriers in real-time to find the optimal shipping option for each package. Address validation uses USPS and international postal databases to correct and standardize addresses before shipping, reducing costly delivery failures. Label generation produces compliant shipping labels for all supported carriers with options for thermal and standard printing. Package tracking provides normalized tracking events across all carriers through a single webhook or polling endpoint. ShipEngine supports international shipping with automated customs forms, harmonized tariff codes, and landed cost estimates. The platform handles complex scenarios including multi-piece shipments, hazardous materials declarations, and return label generation. For marketplace operators, ShipEngine enables multi-seller shipping workflows where each seller uses their own carrier accounts through a unified API.