JSON Formatter & Validator
Format, beautify, and validate JSON online for free. Instantly pretty-print minified JSON with syntax highlighting.
About this tool
Our free JSON Formatter and Validator helps developers quickly format minified or unreadable JSON into a clean, human-readable structure. Simply paste your raw JSON data and click Format — the tool validates the syntax, reports any errors with line numbers, and outputs beautifully indented JSON. Works entirely in your browser with no data sent to any server, making it safe for sensitive data. Supports large JSON files and complex nested structures.
How to use JSON Formatter
- 1Paste your JSON: Copy your JSON data and paste it into the input text area on the left.
- 2Click Format: Press the "Format JSON" button to instantly beautify and validate your JSON.
- 3Review errors: If there are syntax errors, they will be highlighted with the line number and description.
- 4Copy the result: Click "Copy" to copy the formatted JSON to your clipboard.
Frequently Asked Questions
What is JSON formatting?
JSON formatting (or pretty-printing) adds indentation and line breaks to compressed JSON data, making it easier to read and debug.
Is this JSON formatter free?
Yes, completely free with no account required. Use it as many times as you want.
Does my JSON data get sent to a server?
No. All processing happens entirely in your browser. Your data never leaves your device.
Can it validate JSON syntax?
Yes. The tool checks for syntax errors and highlights the exact location of any issues.
What is the maximum JSON size supported?
The tool works with large JSON files. Performance depends on your browser, but typical files up to several MB work fine.