Form utilities
Free Form Data Parser
Decode URL-encoded form data into readable JSON, keeping repeated field names as arrays. Paste a request body or query string to inspect it.
Start with the example, or enter your own text.
How to use this tool
- Paste the application/x-www-form-urlencoded body from your request log, or a full URL with a query string.
- Parse it to see each field decoded, with repeated names grouped into arrays.
- Copy the JSON to compare against what your backend expects.
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Open tool ↗Frequently asked questions
Form data parser
questions.
Why do checkbox values appear as an array?
Each ticked checkbox sends the same field name again. The parser groups them so you can see every selected value in one place.
Can I paste a whole URL?
Yes. When the input starts with a URL, only the query string after the question mark is parsed.
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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