API Tester
Test REST API endpoints live in your browser with custom HTTP methods, headers, query params, and body.
Configure. Run. Inspect.
Requests run only when you click Run. Browser CORS restrictions apply; remote responses are never simulated.
Output
How to Use API Tester
Select HTTP method (GET, POST, PUT, PATCH, DELETE).
Enter your API URL endpoint.
Add optional headers, query params, or JSON request body.
Click 'Send Request' to inspect live status, headers, and response payload.
Frequently Asked Questions
Can I test endpoints with CORS restrictions?
Browser security rules (CORS) apply to direct client-side fetch requests. Ensure your target API allows Access-Control-Allow-Origin: * or test public test APIs (like JSONPlaceholder).
Is any authentication data stored or logged?
No. Everything executes 100% inside your local browser memory. No headers or bearer tokens are saved on any server.
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