JSON Formatter

Free online JSON formatter and validator. Beautify, minify and validate JSON with clear error messages. No signup, works in your browser.

How to use the JSON Formatter

  1. Paste your JSON into the input box on the left.
  2. Click "Format" to beautify it, or "Minify" to compress it into one line.
  3. If the JSON is invalid, an error message shows the exact position of the problem.
  4. Click "Copy" to copy the result to your clipboard.

Frequently asked questions

Is my JSON data sent to a server?

No. All formatting and validation happens locally in your browser using JavaScript. Your data never leaves your device.

What happens if my JSON is invalid?

The validator shows a descriptive error message including the line and position where parsing failed, so you can fix it quickly.

Is there a size limit for formatting JSON?

There is no hard limit. Since everything runs in your browser, performance depends on your device, but multi-megabyte JSON files typically work fine.

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