Developer
JSON Formatter
Free online JSON formatter, validator, and minifier — paste JSON to format with proper indentation, validate syntax, or minify. Runs entirely in your browser.
How to use JSON Formatter
- Paste JSON.
- Click Format, Minify, or Validate.
- Copy the result.
Frequently asked questions
Is my JSON sent to any server?
No. Everything runs in your browser — your data never leaves your device.
What does 'Invalid JSON' mean?
Usually a missing comma, unquoted key, trailing comma, or unescaped quote. The validator highlights the line for you.