JSON Formatter & Validator
Paste or type JSON to format, validate, and minify. 100% client-side — nothing leaves your browser.
Input
Output
Frequently Asked Questions
Is my JSON data sent to any server?
No. All processing happens in your browser using JavaScript. Your data never leaves your device.
What JSON formats are supported?
Standard RFC 8259 JSON. Objects, arrays, strings, numbers, booleans, and null are all supported.
How do I format messy JSON?
Paste your JSON into the input area and click Format. It will pretty-print with consistent indentation.
What is JSON minification?
Minification removes all unnecessary whitespace from JSON, reducing file size for transmission. Click Minify to compress.
Why is my JSON invalid?
Common errors include trailing commas, single quotes, missing quotes around keys, and comments (not allowed in JSON). Click Validate to see the exact error.