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

Requestly is an open-source tool that simplifies API development, testing, mocking, and integration for developers and QAs.

Selenium automates browsers. That's it! What you do with that power is entirely up to you.

Real API Design-first Development Platform Design. Debug. Test. Document. Mock. Build APIs Faster & Together.

Testing and validating REST services in Java is harder than in dynamic languages such as Ruby and Groovy. REST Assured brings the simplicity of using these languages into the Java domain.

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.