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JSON Formatter

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What is JSON?

JSON (JavaScript Object Notation) is a lightweight data format used to exchange structured data between services and applications.

This tool helps you format (pretty-print) JSON for readability or minify JSON to reduce size for storage and network transfer. Processing runs locally in your browser.

How to use the JSON Formatter

  1. Paste your JSON into the Input field.
  2. Click Format to pretty-print JSON with indentation.
  3. Click Minify to remove whitespace and shrink the JSON.
  4. Use Copy to copy the result.

Common JSON formatting errors

  • Trailing commas are not valid in standard JSON.
  • Keys and string values must use double quotes.
  • Unescaped quotes inside strings will break parsing.
  • Missing commas between fields or array items.

JSON Formatter FAQ

Does this tool validate JSON?
If your input is invalid JSON, the formatter will show an error. After formatting succeeds, the output is valid JSON.
Is my JSON sent to the server?
No. Formatting happens in your browser. We do not store or transmit your input.
What’s the difference between JSON and JavaScript objects?
JSON is a data format with strict rules (double quotes, no functions). JavaScript objects are more flexible and allow additional syntax.
Can I format huge JSON files?
Large inputs may be slow depending on your device. For very large files, try splitting the JSON or formatting smaller parts.