API Tester
Craft method, URL, headers, and body, then send REST API requests directly from your browser. Inspect status codes, timing, and response bodies for public APIs and endpoints you own or have permission to call. CORS and mixed-content rules apply — there is no backend proxy and no way to bypass browser security.
Runs entirely in your browser. Your data never leaves this device.
- GET POST PUT PATCH DELETE HEAD
- Custom headers and request body
- Status code and timing display
- CORS-aware REST API client
- No server-side proxy
How it works
- Set method, URL, headers, and body for a REST API you own or have permission to call.
- Send the HTTP request from your browser (CORS and mixed-content rules apply). Private IPs and localhost are blocked in this UI.
- Inspect status code, timing, and response body. Nothing is proxied through SnapUtilsPro servers.
Key features
- GET POST PUT PATCH DELETE HEAD
- Custom headers and request body
- Status code and timing display
- CORS-aware REST API client
- No server-side proxy
FAQ
Is this a free online API tester / REST client?
Yes. It is a browser-based HTTP request client for quick REST API checks — methods, headers, body, status, and timing — with no backend proxy.
Why CORS errors?
Browsers block cross-origin calls unless the API allows your origin. Use public test APIs or enable CORS on APIs you control. There is no backend proxy to bypass CORS.
Can I scan third-party APIs?
No. Only send requests to systems you own or have explicit authorization to test. Unauthorized scanning may be illegal and is not supported.
Why are localhost and private IPs blocked?
To reduce accidental SSRF-style probing from a shared web UI. Use Postman, curl, or a desktop client for local development APIs.
Are requests proxied or logged by SnapUtilsPro?
No. Requests go directly from your browser to the destination. We do not operate a request proxy.
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