Free JSON Formatter
Format, minify, and validate JSON instantly. Free, no signup, works in your browser.
Related Tools
Get notified of new tools
New tools every week. No spam, unsubscribe anytime.
How to Format JSON Online
Paste your JSON into the input field and click Format to pretty-print it with proper indentation. Use Minify to remove all whitespace for compact transmission. Click Validate to check whether your JSON is syntactically correct. All processing happens in your browser using the native JSON.parse and JSON.stringify methods.
Why Use Our JSON Formatter?
Developers constantly work with JSON in API responses, configuration files, and data exchanges. Our formatter runs entirely in your browser — your data never leaves your device. It's free, handles large JSON files, and provides clear error messages that pinpoint exactly where your JSON syntax is broken.
Frequently Asked Questions
Is my JSON data safe? Yes. All processing happens locally in your browser. Nothing is sent to any server.
What JSON errors does it detect? It catches all syntax errors: missing commas, unquoted keys, trailing commas, mismatched brackets, and invalid values.
Can it handle large JSON files? Yes. Since it uses native browser JSON.parse, it can handle files up to several megabytes depending on your browser and device memory.