JSON Formatter / Validator
Format, validate, and minify JSON instantly. Get error messages with line numbers — free, private, no sign-up required.
JSON is processed entirely in your browser — your data is never sent to any server. Press Ctrl+Enter to format quickly.
Frequently asked questions
What does a JSON formatter do?
A JSON formatter takes raw or minified JSON and rewrites it with consistent indentation so it is easy for humans to read. It also validates the syntax and reports the exact line and column of any errors.
When is JSON minification useful?
Minification removes all whitespace from JSON, reducing payload size for faster API responses and lower storage costs. Use the Minify button to produce a single-line compact version suitable for production environments.
Is my JSON data sent to a server when I use this tool?
No. All formatting and validation is performed in your browser using JavaScript. Your data never leaves your device, making this tool safe to use with sensitive or proprietary JSON payloads.