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

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.

Playwright enables reliable end-to-end testing for modern web apps.

Voiden is a developer-first API client with local storage, Git-integrated, all based on markdown + offline support.

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.

Swagger UI allows anyone — be it your development team or your end consumers — to visualize and interact with the API’s resources without having any of the implementation logic in place