JSON Formatter

How to use the JSON Formatter

1. Paste or type your JSON into the JSON input box.
2. Choose an indentation style: 2 spaces, 4 spaces, 1 space, or Tab.
3. Click Format to beautify, Minify to compress onto fewer lines, or Validate to check whether the JSON is valid.
4. Review the result in the Formatted JSON area.
5. Use Copy to place it on the clipboard, Download to save a file, or Clear to start again.

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What it is for

JSON is the usual way APIs, config files and many web apps exchange structured data. When it arrives as one long line, or with inconsistent spacing, it is hard to read and easy to break. This formatter turns messy JSON into a clear, indented layout so you can see objects, arrays and nested fields at a glance.

Format adds line breaks and indentation according to the option you picked. Minify does the opposite: it strips unnecessary whitespace so the payload is smaller for transfer or storage. Validate checks the syntax (missing commas, unquoted keys, trailing commas and similar mistakes) and tells you whether the text is valid JSON without changing it beyond what you ask for.

Typical uses include cleaning up a response from an API, checking a package.json or settings file before you commit it, or preparing a compact string for an HTTP body. If you work with text as well as data, the Case Converter and Word Counter sit in the same browser-only toolkit.

Why it runs in your browser

Everything happens on your device. Your JSON is not uploaded to Catpool’s servers, so drafts, tokens, customer records and other sensitive payloads never leave the tab. That matters when you are formatting real production data rather than a sample from a tutorial.

Common questions

What is the difference between format and minify?

Format (beautify) spreads the JSON over multiple lines with indentation so it can be easily understood. Minify removes that whitespace so the same data takes less space. Both keep the same structure and values; only the presentation changes.

What does Validate do?

Validate checks that the input follows JSON rules. If something is wrong, for example a missing brace or a single-quoted string, you get feedback instead of silently accepting broken data. Fix the issue, then format or minify as needed.

Which indentation should I choose?

Two spaces and four spaces are the most common in web projects. Tab is useful if your editor or team standard uses tabs. One space is compact but still readable. Pick whatever matches the file or codebase you are editing.

Can I download the result?

Yes. After formatting or minifying, use Download to save the output as a file. Copy puts the same text on your clipboard for pasting into an editor or terminal.

Does the tool change my data values?

No. It only adjusts whitespace and layout (or reports validity). Numbers, strings, booleans and nulls stay as they were, provided the original JSON was valid.

Related: Developer, Case Converter.