Form endpoint tester

Preview the GET URL or POST payload a form would send, without making a network request.

Request preview

Preview exactly how a browser encodes form fields for GET and POST submissions. Add name/value pairs and inspect the URL-encoded payload without sending a network request.

No request is sent

This is a payload builder and inspector, safe for dummy or sensitive values.

Browser-compatible encoding

URLSearchParams applies standard application/x-www-form-urlencoded encoding.

GET and POST

GET places fields in the query string; POST keeps the same encoding in the request body.

Frequently asked questions

Can it verify that my real endpoint works?

No. It deliberately makes no network request; use the generated cURL command when you are ready to test.

Can fields repeat?

Yes. Repeated names are preserved in order.

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