ALLYX ONE
100% browser-based · zero uploads

JSON Formatter

Format, validate, and minify JSON online for free — paste raw JSON to instantly beautify it with configurable indentation and precise error detection. No sign-up, no account, nothing leaves your browser.

Indent
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How It Works

1

Paste your JSON

Drop any raw or minified JSON into the input panel. Your data stays entirely in your browser — nothing is sent anywhere.

2

Pick your mode

Choose Format to beautify, Minify to compress, or Validate to check for errors. The result appears instantly — no button to press.

3

Copy or fix errors

Click Copy to grab the output. If your JSON has a syntax error, you'll see the exact location and reason so you can fix it fast.

How to Format JSON Online

  1. Paste or type your raw JSON into the left-hand input panel.
  2. Select Format to beautify, Minify to compress, or Validate to check for errors. The output updates immediately.
  3. Click Copy to send the formatted JSON to your clipboard. If there's a syntax error, the error message tells you exactly what went wrong.

Features

  • Instant formatting: Output updates as you type — no button to press.
  • 2-space and 4-space indentation: Choose the style that matches your codebase.
  • Minification: Strip all whitespace to produce the smallest possible JSON payload for APIs or storage.
  • Validation with error messages: Precise error messages show the type of syntax error and its position in the string.
  • Load sample: A built-in sample JSON lets you test the tool instantly.
  • Your data stays private: Everything runs in your browser using native JSON.parse() and JSON.stringify() — nothing is uploaded, stored, or logged.
  • No account required: Open the page and start formatting straight away.
  • Works offline: Pure JavaScript — once the page has loaded, no network connection is needed.

Frequently Asked Questions

Is my JSON data uploaded to your servers?

No. All processing happens locally in your browser using JavaScript's built-in JSON.parse() and JSON.stringify(). Your data never leaves your device and is never sent to or stored on any server.

Is this JSON formatter free to use?

Yes, completely free — no account, no sign-up, and no usage limits.

What is the difference between Format and Minify?

Format (beautify) adds indentation and line breaks to make JSON human-readable. Minify removes all unnecessary whitespace to produce the smallest possible output — useful for APIs and production payloads.

What happens if my JSON has an error?

The tool immediately highlights the input in red and shows the browser's native error message, which typically includes the type of error and the character position where parsing failed.

Does the JSON formatter work offline?

Yes. The tool is pure client-side JavaScript — once the page has loaded, it works without an internet connection.

What indentation options are available?

You can choose between 2-space and 4-space indentation in Format mode. Both are widely used conventions — 2 spaces is common in JSON configs and JavaScript projects, while 4 spaces is common in Python and other languages.