Kritools logo Kritools

JSON Formatter

Paste JSON to format, validate, or minify it — with clear error messages showing exactly where a problem is.

Empty
Input
Output
Formatted JSON will appear here
Invalid JSON
Runs in your browserYour JSON is never sent anywhere — parsing and formatting happen locally.
Clear error locationWhen JSON is invalid, see the line and character where the problem starts.
Free, no sign-upFormat or minify as much JSON as you need — no limits.

How to use the JSON Formatter

  1. Paste your JSON. Drop raw or minified JSON into the input box on the left.
  2. Pick an action. Tap Format to pretty-print with indentation, or Minify to strip whitespace for a compact output.
  3. Check errors instantly. If the JSON is invalid, the tool highlights the exact line and character where the problem starts, instead of a vague error.
  4. Copy the result. Use the copy button to grab the formatted or minified output with one tap.

Everything runs locally in your browser — no JSON is ever sent to a server, which makes this safe for API responses, config files, or any data you'd rather not upload anywhere.

Features

Precise error locations

Points to the exact line and character of a syntax error instead of a generic failure message.

Format or minify

Switch between pretty-printed, indented JSON and a compact minified version in one click.

100% client-side

Nothing you paste is uploaded, logged, or stored — it never leaves your browser.

No sign-up, no limits

Free to use with no account and no artificial size caps.

Frequently asked questions

No. Formatting, validation, and minification all happen locally in your browser. Nothing you paste is transmitted or stored.

When your JSON is invalid, the tool points to the exact line and character position of the problem instead of a generic error message.

Yes. Alongside pretty-printing, the tool can minify JSON by stripping whitespace for a compact output.