JSON Formatter
Paste any JSON to beautify it with proper indentation, validate its syntax with pinpoint error positions, or minify it for production. Everything runs locally in your browser — your data never leaves your device.
How it works
The tool parses your input with JSON.parse. On success it re-serializes with JSON.stringify using your chosen indent (or no indent to minify). On failure it surfaces the parser's error message, including the exact line and column where the syntax broke.
Frequently asked questions
Is my JSON uploaded to a server?
No. Formatting and validation happen entirely in your browser with JavaScript. Nothing is sent anywhere.
Why does my JSON fail to parse?
Common causes: trailing commas, single quotes instead of double quotes, unquoted keys, or comments (standard JSON doesn't allow them).