The Ultimate Online API Tester
Testing APIs shouldn't require downloading heavy desktop applications like Postman or Insomnia. Our Free API Tester Online is designed for modern developers who need to quickly execute RESTful HTTP requests, inspect headers, and format JSON responses directly in the browser. Because we route your requests through an advanced backend proxy, you completely bypass browser CORS restrictions—meaning you can test any public or private API seamlessly.
Frequently Asked Questions
Traditional browser-based fetch tools fail when an API server doesn't send
Access-Control-Allow-Origin headers. Our tool sends your request payload to our secure StoryBrain AI backend proxy, which executes the request from our servers and streams the pure response back to you. This guarantees 100% success without CORS blocking.
Yes. The proxy request is stateless and ephemeral. We do not log, store, or cache your request bodies, tokens, or API responses. The transaction lives only for the milliseconds it takes to route the traffic.
Our HTTP client fully supports GET, POST, PUT, DELETE, and PATCH methods. You can also inject custom headers, authorization tokens (Bearer), and raw JSON payloads.