Free tool
Test an HTML form before it goes live
Paste a form to see which fields the browser will send, what the request looks like, and the mistakes that silently drop answers. Everything runs in your browser: nothing is submitted and nothing is sent to us.
How it works
The tester parses your HTML the way a form backend sees it: only fields with a name are sent, disabled fields are skipped, checkboxes and radio buttons only count when checked, and a file field needs POST with multipart encoding. It flags the problems that make answers disappear, the ones that hurt keyboard and screen-reader users, and the ones that put data in the URL.
It never submits the form and never contacts the address in its action, so it cannot act as a relay. To test a real submission end to end, create a free Formward form and post to it from your own page.
Questions
- Why is a field missing from the submission?
- The browser only sends controls that have a name attribute and are not disabled. An input with only an id or a placeholder is never sent. Checkboxes and radio buttons are sent only when they are checked.
- Should a form send JSON or form data?
- A plain HTML form sends URL-encoded data, or multipart data when it has a file field. JSON is only sent when your own JavaScript builds the request. Formward accepts all three.
- Why does my file upload arrive as just a file name?
- The form needs method="post" and enctype="multipart/form-data". Without them the browser sends only the name of the file.
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