Abstract: A method and system for generating an API request message for an API service application is provided. The API service application is stored within a service owner (SO) computer device and includes a memory device for storing data and a service provider (SP) computer system that includes a processor and an open application programming interface (API) platform. The SP computer system in communication with the memory device and the SO computer device. The SP computer system is programmed to receive from a developer a plurality of selections of parameters defining an API service request, generate an API request message for a specific API service using the received parameter selections, the API request message including the received parameter selections in a predetermined format required by the specific API service, generate a response to the generated API request message, and display the generated API request message and response on a single webpage.