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API Tester

Developer Tools

Test REST APIs with visual interface.

⚡ Instant🌐 Online lookup🆓 Free, no sign-up👥 For developers
Requests are sent straight from your browser to the API address you enter; they do not pass through FreeToolsVerse.

What API Tester does

API Tester lets you send REST API requests with custom headers, HTTP methods, and request bodies, and see the response status, timing, and size — a lightweight alternative to a full API client for quick checks.

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Reviewed by the FreeToolsVerse team · Last updated · How we check our tools

How to use API Tester

  1. Enter the API endpoint URL and choose the HTTP method
  2. Add headers and a request body if needed
  3. Click Send to make the request
  4. Review the response status, time, and body

Who should use it

Made for developers. Typical uses:

  • Quickly testing an API endpoint without installing a full API client
  • Debugging why an API call is returning an unexpected status code
  • Checking response times for a specific endpoint

Frequently asked questions

Which HTTP methods are supported?
Common methods like GET, POST, PUT, PATCH, and DELETE.
Can I add custom headers?
Yes, add any headers your API request needs, like authentication tokens or content-type.
Is it free to use?
Yes, completely free.
Are my requests sent through your servers?
Requests go directly from your browser to the API endpoint you specify — not proxied through our servers.
Can I test authenticated APIs?
Yes, add an authorization header with your token or credentials as the API requires.

Learning resources

Explore more in Developer Tools, read the guides and articles, or see how we test our tools.

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