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

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

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

Hand-crafted lightweight Rest Client for testing APIs. Supports collections, environments, git collaboration and local storage.

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

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.