Mockoon is the easiest and quickest way to design and run mock REST APIs.

Design, debug, and test APIs locally or in the cloud

RapidAPI for Mac is a full-featured HTTP client that lets you test and describe the APIs you build or consume. It has a beautiful native macOS interface to compose requests, inspect server responses, generate client code and export API definitions.

Postman is an API platform for building and using APIs. Postman simplifies each step of the API lifecycle and streamlines collaboration so you can create better APIs—faster.

Simulate APIs, integrations, and environments at enterprise scale.

Hoppscotch is an open-source API development ecosystem that helps you create and test your API requests saving precious time in development.