JSON Formatter

Format, validate and minify JSON instantly with clear syntax error messages.

This tool runs entirely in your browser — your data is never uploaded to a server.

How to Use

  1. Paste your JSON into the input box.
  2. Click "Format / Validate" to pretty-print it, or "Minify" to compress it.
  3. If your JSON is invalid, the exact error and position will be shown.

Features

  • Real JSON parsing — catches genuine syntax errors, not guesses.
  • Pretty-print with 2-space indentation or one-line minify.
  • Copy or download the formatted result as a .json file.
Please note: Very large JSON files (several MB+) may be slow to format in some browsers since parsing happens on the main thread.

Frequently Asked Questions