Form utilities
Free Form Action Checker
Paste your form HTML to check the action URL, method and encoding. Catch GET submissions, missing HTTPS and file uploads without multipart encoding.
How to use this tool
- Paste your form HTML, including the opening form tag.
- Run the check to review the action, method and enctype attributes.
- Fix the attributes, then submit a test entry to your endpoint.
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Open tool ↗Frequently asked questions
Form action checker
questions.
Why should a form use POST instead of GET?
GET puts every field into the URL, where it ends up in browser history and server logs. POST keeps the data in the request body and has no length limit.
What should the action be for a static site?
Point it at a form backend endpoint. Form Koi gives each form an HTTPS endpoint that accepts POST and multipart submissions from any static host.
Is anything I enter saved or sent to Form Koi?
No. Everything you type or upload stays in this browser tab and is processed locally. Copy or download anything you want to keep before leaving the page.
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