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Paste JSON to pretty-print it with your preferred indentation, minify it for transport, or just find out why it won't parse — the validator reports the exact error. Formatting runs locally, which matters more than it sounds: API responses and config files routinely contain keys, tokens and customer data that shouldn't be pasted into a random website's server.
Frequently asked questions
My JSON is "invalid" but looks fine — what are the usual culprits?
Trailing commas after the last item, single quotes instead of double quotes, unquoted keys, and comments — all legal in JavaScript, all forbidden in strict JSON. The error message points at the offending position.
Is my JSON sent anywhere?
No. Parsing and formatting use your browser's built-in JSON engine; nothing is transmitted. Safe for API payloads containing secrets — though rotating any token you've pasted anywhere is still good practice.
What's the difference between formatting and minifying?
Formatting adds whitespace and line breaks for human reading. Minifying strips every unnecessary byte for machines — same data, smallest size. The byte count of the output is shown either way.