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JSON Formatter/Validator

Format, minify, and validate JSON with calm parse errors and copy-ready output.

Runs locally in your browser. Your input is not uploaded.
Output
Formatted or minified JSON will appear here.

How to use JSON Formatter

  1. Paste JSON into the input area.
  2. Choose Format for readable output or Minify for compact output.
  3. If parsing fails, read the error and check the nearby line and column.

Examples

Copy patterns and edge cases worth checking.

Format compact JSON

{"name":"Ada","tools":["csv","json"]}
{
  "name": "Ada",
  "tools": [
    "csv",
    "json"
  ]
}

Minify formatted JSON

{
  "ok": true
}
{"ok":true}

FAQ

Short answers before you paste real data.

Does this support JSON with comments?

No. It validates standard JSON only, so comments and trailing commas are errors.

Can it format large JSON files?

It is designed for pasted JSON payloads. Very large files or multi-megabyte inputs may be limited by browser memory.

Does invalid JSON leave the browser?

No. Validation happens locally.

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