JSON formatter & validator
Beautify, validate, and minify JSON. Paste it in, pick your indentation, and copy clean output.
Format, validate, or minify
Paste JSON and tap Format to pretty-print it with clean indentation, or Minify to strip every unnecessary space for production. If the JSON is malformed, you get a clear error pointing at the problem instead of a silent failure. It all runs in your browser, so even config files or API responses with sensitive values never leave your device.
Why formatting matters
Minified JSON — one long line with no spaces — is efficient for machines but nearly unreadable for people, which makes debugging an API response or a config file painful. Pretty-printing restores the structure: indentation shows nesting at a glance, so you can see which fields belong to which object and spot a missing or misplaced value quickly. When you're done reading, minifying again shrinks the payload for transmission, where every byte counts.
Catching the common mistakes
Most JSON errors come from a handful of culprits: a trailing comma after the last item, single quotes instead of double quotes, unquoted keys, or a missing bracket. JSON is stricter than JavaScript object syntax, which trips people up constantly. Running text through the formatter is the fastest way to confirm it's valid before you paste it somewhere that will reject it less helpfully. Need to turn that JSON into a spreadsheet? The JSON to CSV converter handles arrays of objects.