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

Free & OpenSource REST API Testing Tool for all levels in a Test Pyramid

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.

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

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

Automate API workflows. Chain HTTP requests. Validate. Zero code.