A LITTLE LESS BUSYWORK
JSON Formatter and Validator - Beautify or Minify JSON
Turn a dense API response or configuration into readable JSON. Validate it, choose your indentation, or minify it for transport without sending the content to a server.
Free to use / Runs on your device / No account neededNo uploads, saved drafts, or public sharing. Up to 1 million input characters and 100 formatting levels. Number literals are preserved, including large integers and exponent notation. Copying requires clipboard permission; you can also select the output manually.
How to use it
- Paste JSON into the input editor.
- Choose an indentation style or minified output, then validate and format.
- Review the output, copy it, or download a JSON file.
A few useful answers
Will it repair invalid JSON automatically?
No. Invalid syntax is reported so you can fix it deliberately. Automatically guessing missing quotes or changing values can alter meaning.
Are large integers preserved exactly?
Yes. Syntax is validated, then the original number tokens are formatted without converting them into JavaScript numbers. Large integers, negative zero, and exponent notation remain intact. Input is limited to 1 million characters and pretty-printing to 100 nesting levels.