JSON Formatter
Format, beautify, validate, and minify JSON data instantly. Choose your preferred indentation style and get clean, readable output. All processing happens in your browser -- your data never leaves your device.
Supports 2-space, 4-space, and tab indentation
JSON Input
Paste or type JSON data to format, validate, or minify
How to Use This JSON Formatter
Paste Your JSON
Copy your JSON data from an API response, config file, or any source and paste it into the input area above.
Choose Indentation
Select your preferred indentation style: 2 spaces (compact), 4 spaces (spread out), or tabs (configurable in your editor).
Format or Minify
Click Format to beautify with indentation, or Minify to compress. Copy the result to your clipboard with one click.
How JSON Formatting Works
JSON.parse(input) → JSON.stringify(parsed, null, indent)JSON formatting follows a two-step process: first the raw text is parsed into a JavaScript object tree, then it is serialized back to text with the desired whitespace settings.
Step 1: Parse the JSON string into a data structureStep 2: Validate syntax (missing commas, brackets, quotes)Step 3: Re-serialize with chosen indentationMinify: Re-serialize with zero whitespaceKey details about JSON syntax:
- Keys must be double-quoted -- single quotes and unquoted keys are not valid JSON (though they work in JavaScript)
- No trailing commas -- the last item in an array or object must not have a comma after it
- No comments -- JSON does not support // or /* */ comments (use JSONC or JSON5 for that)
- Strings must use double quotes -- single-quoted strings are a common source of validation errors
This tool processes everything client-side in your browser. No data is ever sent to a server, making it safe for sensitive or proprietary JSON data.
Frequently Asked Questions
What is JSON formatting?
JSON formatting (also called beautifying or pretty-printing) adds proper indentation and line breaks to compact JSON data, making it easier to read and understand. The data itself remains identical -- only whitespace is changed. This is the reverse of minification, which removes all unnecessary whitespace.
How do I validate JSON?
Paste your JSON into the input area and click "Format." If the JSON contains syntax errors, the tool will display a detailed error message with the approximate line and column number where the problem was detected. Common errors include missing commas, unquoted keys, trailing commas, and single quotes instead of double quotes.
What is the difference between 2-space and 4-space indentation?
Both are valid formatting styles. 2-space indentation produces more compact output and is common in JavaScript/TypeScript projects and npm package.json files. 4-space indentation is more spread out and is common in Python projects and many configuration files. Tab indentation lets each developer configure their editor to display tabs at their preferred width.
Why would I minify JSON?
Minifying JSON removes all unnecessary whitespace (spaces, tabs, newlines), reducing file size. This is useful for API responses, configuration files sent over networks, and storing JSON in databases where readability is not needed. Minified JSON is functionally identical to formatted JSON.
Is my data safe when using this tool?
Yes. All JSON processing happens entirely in your browser using JavaScript. Your data is never sent to any server. Nothing is logged, stored, or transmitted. You can verify this by using the tool with your browser in offline mode after the page loads.
Privacy Notice
This JSON formatter runs entirely in your web browser. Your data is never uploaded, stored, or processed on any server. All formatting, validation, and minification operations use standard browser JavaScript APIs. You can safely use this tool with sensitive data, API keys, or proprietary configurations.