Form to Webhook Builder is a complete front-end tool for designing a form and wiring it to a webhook. Drag fields from a palette onto a canvas, set labels, keys, validation rules and custom error messages, and watch the exact JSON payload update as you fill in the live preview. When the form is ready, copy a self-contained HTML snippet that includes the markup, styles, validation and a retrying fetch() call.

The webhook tab covers the part builders usually skip: URL, method, headers, an optional HMAC signing secret, retries with exponential backoff and a timeout. A mock test sender lets you simulate a 200, a flaky 503, a rate limit, a 400, a timeout or a network error with adjustable latency, then read each attempt, the request and the response in a log. Nothing leaves the browser unless you switch on Live mode.

It is a plain HTML, CSS and JavaScript project. Open index.html and it works, with forms saved in localStorage. Everything that would talk to a server is isolated in js/api.js with clear TODO comments, so connecting your own backend takes minutes.

It is honest about its limits: file fields send names only, and signing belongs on your server.