Why do I see CORS errors in the browser?
Cross-origin responses need Access-Control-Allow-Origin and related headers. Use the CORS Checker on this site to diagnose.
API Request Tester
DevTools API Request Tester sends GET, POST, and other HTTP requests from your browser and shows status, headers, and body—quick REST API debugging without installing Postman.
API Request Tester
Send HTTP requests from the browser to test REST APIs and inspect response status and body.
About this tool
Verify URLs, auth headers, and JSON bodies during backend integration. Responses display status code, headers, and payload for inspection.
How to use
- Choose HTTP method and target URL.
- Add headers and body if needed.
- Click Send Request and review the response.
FAQ
Does it support file uploads?
Full multipart upload is planned for a future release. Current builds focus on JSON and plain-text APIs.
Are requests proxied?
Browser requests go directly to the target URL subject to CORS. Some targets may block browser-origin calls.
Is this tool free?
Yes. No registration required.
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