Beautify, validate and minify JSON right in your browser.
The basics
What does this tool do?
Paste any JSON into the input box. It validates it as you type, and the buttons let you Beautify (pretty-print with indentation and colour), Minify (strip all whitespace into one compact line), and Sort keys (alphabetise every object's keys, recursively). Valid data also shows a quick summary — object, array, key and value counts.
How do I read the error message?
If the JSON is invalid, the status bar turns red and points to the exact line and column where parsing failed. The most common culprits are trailing commas, single quotes instead of double quotes, unquoted keys, and missing brackets or braces.
Can I change the indentation?
Yes — use the Indent dropdown to switch between 2 spaces, 4 spaces, or a real tab character. Changing it re-formats the output immediately.
Tips & limits
What counts as valid JSON?
Strict JSON per the specification: double-quoted keys and strings, no trailing commas, no comments, and no undefined, NaN or Infinity. If you have "JavaScript-style" object text with those features, this tool will flag them so you can fix them.
Are big files OK?
It handles typical API responses and config files comfortably. Very large documents (many megabytes) may format slowly because everything runs on your own device — there is no server to offload to.
Keyboard shortcuts?
Press Ctrl+Enter (or Cmd+Enter) in the input box to beautify without reaching for the mouse.
Privacy
Is my JSON uploaded anywhere?
No. All parsing, formatting and validation happen locally in your browser using the built-in JSON engine. Nothing is sent to a server, and reloading the page clears everything.
