JSON Formatter

Format, validate and minify JSON instantly. Paste an API response or config file and get clean, readable output — or a precise error message telling you exactly where the problem is.

How to use this tool

  1. Paste your JSON into the input box.
  2. Choose an indentation style (2 spaces, 4 spaces or tabs).
  3. Press “Format” to beautify, “Minify” to compress, or “Validate” to check.
  4. If the JSON is invalid, the error message shows the line and column.
  5. Copy the result or download it as a .json file.

Key features

  • Clear parse errors with line and column numbers.
  • Three indentation styles to match your project.
  • One-click minify for production payloads.
  • Everything runs in your browser — JSON never leaves your device.

Frequently asked questions

No. Formatting and validation happen entirely in your browser with JavaScript. Your data never leaves your device.

When JSON cannot be parsed, we show the parser's message along with the line and column where the problem starts — usually a missing comma, an unquoted key or a trailing comma.

Only whitespace changes. Keys, values and their order are preserved exactly; minifying removes all optional whitespace.

Processing is local, so there is no server limit — even multi-megabyte files are handled by your browser.

This tool runs entirely in your browser — your data is never sent to or stored on our server.

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