Postman

Postman is a platform for building, testing, documenting and publishing APIs. Its client sends HTTP, GraphQL, gRPC, WebSocket and MQTT requests from a single interface, and requests are grouped into collections that can be shared and run as a suite. Environments hold sets of variables, so the same collection can be pointed at a different target without editing the requests themselves.

Testing is done in JavaScript. Pre-request and post-response scripts run around every request, tests are written against a built-in snippet library, and the Collection Runner chains requests, runs them in a set order and logs the results. The same collections run unattended in two other places: Newman and the Postman CLI execute them inside a CI/CD pipeline, and monitors run them on a schedule, support multiple regions and can be restricted with static IP allowlisting. The Postman CLI also lints API schemas and performs security and governance checks.

Mock servers return canned responses, so a client can be built before the real API exists. Postman Flows builds runnable workflows on a visual canvas, can embed AI request blocks, and comes with a gallery of more than 100 prebuilt templates. Workspaces come in personal, internal, partner, multi-partner and public forms, and Postman runs a Public API Network for shared APIs alongside a Private API Network for internal ones.