{ } JSON Formatter & Validator

No. This formatter runs entirely in your browser using the native JSON parser. Your data never leaves your device — nothing is uploaded, stored or logged.

Formatting only changes whitespace to make JSON readable. Validating checks the syntax is actually correct JSON. This tool does both: if your input parses, the output is formatted and confirmed valid; if not, you get the exact error location.

Yes. Click Minify to strip all whitespace and produce the most compact valid JSON — handy for API payloads and config files where every byte counts.

The usual suspects: trailing commas after the last item, missing quotes around keys, unclosed brackets, or single quotes instead of double quotes. The validator reports the exact character position so you can fix it in seconds.

Yes — completely free, no sign-up, no usage limits and no watermarks. It works offline too, once the page has loaded.