Best API Development & Testing Tools
Anything with an API spends its life being poked at. These are the clients you test with, the tunnels that expose localhost to a third-party webhook, and the gateways that keep those callbacks reliable when the other side retries badly.
- 1PostmanFreemium
The industry default — collections, environments, and shared workspaces your whole team can use.
The collaborative API platform — design, test, document.
- 2InsomniaFreemium
Lighter than Postman and open source, with a design-first workflow for OpenAPI specs.
Open-source API client and design platform from Kong.
- 3HoppscotchFree
Runs in a browser tab with nothing to install — the quickest way to fire one request.
Open-source web-based API client — Postman alternative.
- 4BrunoFree
Stores collections as plain files in your repo, so API requests get reviewed like code.
Open-source, Git-friendly API client.
- 5ngrokFreemium
The standard way to expose localhost to a real webhook while you debug it.
Secure tunnels to expose localhost to the internet.
- 6HookdeckFreemium
Sits in front of your webhook endpoints to queue, retry, and replay deliveries you would otherwise lose.
Webhook gateway — receive, transform, and replay reliably.
- 7sherFreemium
Share your localhost with the world instantly via secure tunnels.
- 8RapidAPIFreemium
Discover, connect, and manage thousands of APIs in one marketplace.
- 9YokuFreemium
Modern API documentation and testing platform for developer teams.
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