Hoppscotch Community Edition is an open-source API development and testing tool for REST, GraphQL, WebSocket, SSE, MQTT, and Socket.IO with collections and environments.

80.1k stars6.1k forksMITlast commit Actively maintained
HTTPie is a developer tool for making HTTP requests and testing APIs. It offers a command-line client and a web-based API client to compose requests, manage collections, and support collaborative API testing workflows.
Hoppscotch Community Edition is an open-source API development and testing tool for REST, GraphQL, WebSocket, SSE, MQTT, and Socket.IO with collections and environments.

80.1k stars6.1k forksMITlast commit Actively maintained
Open-source API client and HTTP interceptor to test APIs, modify requests and responses, and create API mocks for faster development and debugging.

6.8k stars700 forkslast commit Actively maintained
Every option on this page is open source and free to run on your own hardware, so you own the data and there is no subscription to cancel. 2 of 2 shipped a commit in the last six months. Licences in this list: MIT. In exchange you take on hosting, backups and updates yourself.
Browse everything in API Development, Mocking & Testing.