Why did my request fail with no other explanation?

The most common cause by far is CORS: browsers block a web page from reading the response of a cross-origin request unless the target server explicitly opts in with an Access-Control-Allow-Origin header. This isn't a limitation of this tool specifically — it applies to any browser-based REST client, and is exactly why desktop tools like Postman or curl (which aren't running inside a browser) don't hit it.

Is this the same as Postman or Insomnia?

It covers the core request/response loop (methods, headers, body, formatted JSON), but as a browser-based tool it can't bypass CORS the way a desktop app can, and it doesn't support collections, environments, or scripting. For APIs you control, you can enable CORS on the server to test them here.

Is my request data sent to your servers?

No — the request goes directly from your browser to the URL you entered via the standard Fetch API. We never see the URL, headers, body, or response.

Does it support GraphQL or WebSockets?

No — this is a plain REST/HTTP client. GraphQL APIs that accept POST with a JSON body will work, but there's no query-specific tooling.

REST API Client

Send an HTTP request to any REST API and inspect the status, headers, timing and body of the response — a lightweight Postman alternative that runs entirely in your browser, with nothing routed through our servers.

Headers

Requests are sent directly from your browser to the URL you enter — nothing passes through our servers. Because of this, requests to APIs that don't explicitly allow cross-origin browser requests (CORS) will fail; this is a browser security restriction that applies to every browser-based REST client, not just this one.

Processing happens locally in your browser. Nothing you enter is uploaded.

How It Works

Choose a method, enter a URL, and optionally add headers and a request body. Click Send. The response status, timing, size, headers and body appear below, with JSON automatically pretty-printed. Use "Copy as cURL" to get an equivalent command for a terminal.

The request (method, URL, headers, body) is sent directly from your browser to the target server using the Fetch API — the exact same mechanism a web page uses to call an API, so it's subject to the same browser security rules (CORS, mixed content).

Example

GET https://jsonplaceholder.typicode.com/todos/1 (a public test API) returns a 200 OK with a small JSON object — click Send on the pre-filled example to see it work immediately.

Frequently Asked Questions

Why did my request fail with no other explanation?: The most common cause by far is CORS: browsers block a web page from reading the response of a cross-origin request unless the target server explicitly opts in with an Access-Control-Allow-Origin header. This isn't a limitation of this tool specifically — it applies to any browser-based REST client, and is exactly why desktop tools like Postman or curl (which aren't running inside a browser) don't hit it.
Is this the same as Postman or Insomnia?: It covers the core request/response loop (methods, headers, body, formatted JSON), but as a browser-based tool it can't bypass CORS the way a desktop app can, and it doesn't support collections, environments, or scripting. For APIs you control, you can enable CORS on the server to test them here.
Is my request data sent to your servers?: No — the request goes directly from your browser to the URL you entered via the standard Fetch API. We never see the URL, headers, body, or response.
Does it support GraphQL or WebSockets?: No — this is a plain REST/HTTP client. GraphQL APIs that accept POST with a JSON body will work, but there's no query-specific tooling.

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