JSON Formatter & Validator
Format, validate, and pretty-print JSON with syntax highlighting and error detection.
How to Use This Tool
- Paste your JSON into the input area on the left.
- Click "Format / Prettify" to indent the JSON with 2-space indentation.
- Click "Minify" to remove all whitespace and produce compact JSON.
- If your JSON is invalid, an error message shows the exact problem.
- Click "Copy Output" to copy the formatted result.
How It Works
This tool uses the browser's native JSON.parse() to validate and parse your input, then JSON.stringify() with optional indentation to produce the formatted output. Validation errors from JSON.parse() are surfaced directly so you can identify and fix syntax problems. No data leaves your browser.
Frequently Asked Questions
What is the difference between formatting and minifying JSON?
Formatting (prettifying) adds line breaks and indentation to make JSON human-readable. Minifying removes all unnecessary whitespace to reduce file size, which is useful for network transfer.
Can I format very large JSON files?
Yes, within browser memory limits. Files up to several megabytes work without issues on modern devices.
Will formatting change the data in my JSON?
No. Only whitespace is changed. All keys, values, arrays, and objects remain identical.