API Tester

Send REST requests, inspect JSON responses, and debug APIs from your browser.

Popular tools

Query Parameters

Ready to Send

Enter a URL and click Send to see the response here.

How to use

  1. Choose the HTTP method and enter the endpoint URL.
  2. Add headers and a JSON body when needed.
  3. Click Send and inspect status, headers, and response body.
  4. Copy the response or adjust the request and repeat.

Features

  • Send REST requests, inspect responses, and iterate quickly.
  • Works on desktop and mobile with a scroll-friendly toolbar.
  • Inspect JSON responses with a developer-focused layout.

Related tools

Guides

Read related engineering guides on JsonOnlineParse.

FAQ

Is this API tester free?

Yes. It is free to use and does not require a login for core REST testing.

Can I call localhost APIs?

Browsers block many localhost calls due to CORS. Use a tunnel such as ngrok or configure CORS on your local server.

Is my request data stored?

Requests are assembled and sent from your browser. We do not persist your URLs, headers, or bodies on our servers.

Why did my request fail?

Common causes include CORS, invalid SSL, network blocks, or server errors. Check the status code and response body shown in the panel.