The best API testing tool depends on whether you care more about team collaboration or local sanity. Those priorities do not always align.
Postman is still the standard for shared collections and team onboarding. Bruno is the best API testing tool if you want local files, git-friendly storage, and less platform overhead. Insomnia stays useful when you want a polished client that still feels developer-first.
The short answer
Use Postman for shared team collections, Bruno for local-first API work, and Insomnia when you want a balanced desktop client.
Top picks
Best API testing tools
The collaboration and environment features reduce repeated setup questions on larger teams.
Local files make review, versioning, and repo portability the default instead of an export step.
Insomnia
Developers who want a clean desktop client without committing to a full platform
Visit InsomniaIt keeps a focused request surface while still supporting environments and basic collections.
Why local-first API tools keep gaining fans
API requests are often part of the codebase in practice, even when they live outside it in a GUI tool. Local-first clients fix that by letting collections live in files you can review, version, and move with the repo.
That is the clearest reason Bruno has gained ground. It feels closer to how developers already work.
When Postman still makes more sense
Postman is still stronger when the job includes shared collections, onboarding less technical teammates, and giving everyone the same documented request flows.
If the API is central to cross-team work, Postman still earns the overhead. The platform is heavier, but the collaboration layer is real.
The best tool is usually the one that fits your team shape
Solo developers and small teams often prefer local-first tools because they stay closer to code. Larger teams often choose the tool that makes shared documentation and onboarding easier.
This is less a feature race than a workflow choice. Start with the team shape, then pick the client.
How we tested these API clients
We used all three clients daily across 12 different backend services for four weeks in April 2026. Work included auth flows with rotating tokens, GraphQL introspection, large response inspection, and sharing collections with two non-engineer teammates. Tests ran on Mac and a Windows machine. We tracked how often we had to leave the tool for curl or browser devtools.
Last tested May 2026. We did not test enterprise-scale collection governance or heavy test script automation in depth.