JSON Formatter & Validator

Format, validate and minify JSON with precise, human-readable error messages.

Processed on your device

How to use

  1. Paste your JSON.
  2. Choose Format or Minify — validation runs as you type.
  3. Copy or download the result.

Frequently asked questions

What happens if my JSON is invalid?

You get the parser’s exact complaint with the approximate line, instead of a silent failure — fix it and the output updates immediately.

Privacy

This tool runs entirely in your browser. Your file is processed on your device and is not uploaded to a server.

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