Systems and methods provide shipping services information. In one implementation, a method is provided in which an e-commerce server receives a request for shipping information from an end-user. The e-commerce server generates an extensible markup language (XML) request based on the requested shipping information and sends the XML request to an application programming interface (API) server. The API server determines, based on the XML request, one of a plurality of API modules stored in the API server to process the XML request and generates an XML response based on data included in the XML request. The API server sends the XML response to the e-commerce server, which sends the XML response to the end-user.