Form Data to JSON

HTTP request bodies from HTML forms arrive as a flat stream of percent-encoded key=value pairs — user%5Bname%5D=Ada&port=5432. Reading them is miserable: the nesting is hidden in bracket syntax, the encoding hides the real characters, and repeated keys mean arrays you have to reconstruct yourself.

Convert Form Data to JSON parses urlencoded bodies and readable key=value lines into a proper JSON object. Bracket paths rebuild nested objects and arrays, values are URL-decoded, repeated keys become arrays, and optional auto-typing restores numbers and booleans.

• Both encodings accepted: URL-encoded bodies and plain key=value lines, split on & or newlines.
• Bracket-path parsing: user[name], items[0][name], items[] all become proper JSON structures.
• Repeated keys become arrays: a=1&a=2 yields {"a":["1","2"]}.
• URL decoding: Spaces, &, =, % and Unicode are restored from percent-encoding.
• Optional auto-typing: true, false, null and numbers become native JSON values.
• Defensive parsing: Invalid escapes and malformed pairs never crash the result.
• Pretty output: The result is formatted, readable JSON.
• Private: All processing happens in your browser; nothing is uploaded.

1. Paste the form data — urlencoded body or key=value lines.
2. Toggle auto-typing if values should become booleans and numbers.
3. Review the live output — bracket paths and arrays are rebuilt automatically.
4. Copy or download the JSON object.

Example 1 — Webhook debugging. A developer captures a form-encoded webhook body from server logs and converts it to JSON to inspect the payload structure without decoding percent-escapes by hand.

Example 2 — Integration tests. A QA engineer converts expected form submissions into JSON assertions, with bracket paths and repeated keys preserved exactly as the server sees them.

Example 3 — Framework migration. A team moving from PHP to a JSON API parses existing $_POST dumps through the tool to build equivalent JSON request fixtures.

Example 4 — Troubleshooting forms. A support engineer takes a raw browser request body from devtools, converts it, and sends the readable JSON to the fix team.

• Readable output: Flat encoded pairs become nested, structured JSON.
• Framework-accurate: Repeated keys and bracket paths match server-side parsing behavior.
• Typed values: Numbers and booleans stay native when you want them.
• Zero data movement: The body is parsed locally and never uploaded.
• Instant results: Live output updates with every keystroke.