Developer Lab · Data tools
JSON Formatter & Validator
Validate, pretty-print, and minify JSON locally in your browser.
Paste JSON and select an action to begin.
Maximum input size: 1 MiB. Nothing is uploaded or saved.
Formatting preserves JSON values, but may normalize whitespace and number representations.
How this tool works
It uses the browser's built-in JSON parser. Formatting and minification only happen after successful validation. The original input remains intact when parsing fails.
For sensitive content, double-check that you are using the intended site. All processing happens on this page; the tool does not send your text to a server.