EnabledKeyValue
Response

Hit Send to see the response here

About CORS Restrictions

Some API requests may fail with a CORS error in the browser. This happens when the target server does not include Access-Control-Allow-Origin in its response headers. This is a browser security mechanism — the request does leave your browser, but the response is blocked. To test CORS-restricted APIs, use a server-side proxy, a browser extension that disables CORS, or run the request from your terminal with curl.

APIs listed in the Quick Examples (JSONPlaceholder, GitHub, Open Meteo, Dog CEO) all allow cross-origin requests and work well for testing.

What is API Request Tester?

The API Request Tester is a lightweight, browser-based HTTP client that lets you send GET, POST, PUT, PATCH, and DELETE requests to any REST API endpoint without installing Postman, Insomnia, or any other desktop tool. It is ideal for developers who need a quick way to test an endpoint, verify a response, or debug an integration directly from their browser.

You can set custom request headers such as 'Authorization', 'Content-Type', and any other headers your API requires. For methods that accept a request body (POST, PUT, PATCH), you can enter JSON or form data directly in the body editor. The response panel displays the HTTP status code, response headers, and formatted response body, making it easy to inspect exactly what the server returned.

The tool is especially useful for frontend developers who are integrating with a backend API and want to verify the shape of a response before writing application code. It is also handy for quickly testing webhook endpoints, checking if an authentication token is valid, or debugging CORS issues. Since the tool runs in your browser, requests are subject to the same CORS restrictions as any browser-based client — a useful and realistic constraint when developing web applications.

How to Use API Request Tester

  1. Enter the endpoint URL

    Type or paste the full API endpoint URL, including query parameters if needed.

  2. Configure method and headers

    Select the HTTP method (GET, POST, PUT, etc.) and add any required headers like Authorization or Content-Type.

  3. Add a request body

    For POST or PUT requests, enter your JSON payload in the body editor. Syntax highlighting helps you spot errors.

  4. Send and inspect the response

    Click Send to execute the request and view the status code, response headers, and formatted response body.

Key Benefits

No installation needed

Run directly in any modern browser — no desktop app, no extension, and no account required.

Full HTTP method support

Send GET, POST, PUT, PATCH, and DELETE requests with custom headers and JSON bodies.

Formatted response view

JSON responses are automatically pretty-printed so you can read nested objects and arrays at a glance.

Real browser environment

Requests run through the browser, so CORS behavior matches what your web app will experience in production.

Frequently Asked Questions

CORS errors occur when the target API does not allow requests from browser origins. This is a server-side restriction. You can test APIs with CORS enabled or use a proxy for development.

Yes. Add an Authorization header with your Bearer token, API key, or Basic auth credentials in the headers section.

You can send GraphQL queries by setting the Content-Type header to "application/json" and sending your query as a JSON body with a POST request to your GraphQL endpoint.

No. All requests are executed directly from your browser and nothing is stored on any server. Your API keys and payloads remain private.

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