Open toolkit

Dev Utilities

JSON Formatter / Validator

Paste in JSON to instantly check whether it is valid, see a clear error location if it is not, and reformat it as either neatly indented or fully minified. Useful for cleaning up API responses, config files, or debugging a malformed payload.

  • Files never leave your device
  • Runs entirely in your browser
  • Free, no account needed
Use JSON Formatter / Validator - free

Frequently asked questions

What happens if my JSON is invalid?

The tool shows an error message describing what went wrong and roughly where in the text the problem is.

Can I minify JSON as well as pretty-print it?

Yes, both a readable indented format and a fully minified single-line format are available.

Is my JSON sent anywhere?

No, formatting and validation happen entirely in your browser.

Format or validate JSON - free and instant.

Open JSON Formatter / Validator
  • Files never leave your device
  • No upload required
  • No account needed
  • Unlimited use, always free

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