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

Burp or Burp Suite is a set of tools used for penetration testing of web applications. It is developed by a company named Portswigger who make freely available a Web Security Academy which has a range of lessons on penetration testing.

Built for developers and testers alike, SoapUI is the only open source tool that covers the entire testing spectrum (functional, security, load, mocking).

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.

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