API design and documentation with OpenAPI
Swagger/SwaggerHub is a suite of tools for designing, building and documenting APIs using the OpenAPI Specification, with collaborative editing and mocking.
API testing and documentation
Postman lets developers build, test and document APIs through collections and environments. Writing tests and docs remains largely manual work.
The Git-native API client
Bruno is an open-source API client that stores collections as plain text files for git version control instead of the cloud. It supports REST, GraphQL, gRPC and WebSocket testing.
Collaborative API design platform
Insomnia is an API client for designing, debugging and testing REST, GraphQL and gRPC APIs, with git sync and team collaboration.
Open source API development ecosystem
Hoppscotch is an open-source, web-based API request builder supporting REST, GraphQL, WebSocket and more, usable directly in the browser or self-hosted.
Lightweight REST client for VS Code
Thunder Client is a VS Code extension providing a lightweight, fast REST API client integrated directly into the editor.
All-in-one API development platform
Apidog combines API design, debugging, mocking, automated testing and documentation into one AI-assisted platform, positioned as a full Postman replacement.