JSON formatter & validator
Format, beautify, validate, and minify JSON online. Pinpoint syntax errors by line and column, sort keys, and copy or download the result.
JSON validator
Validate JSON instantly and find errors by line and column, with hints for common mistakes like trailing commas.
How to use JSON validator
Check whether JSON is valid and find exactly where it breaks. Errors point to the line and column, with the offending line highlighted and a hint for common mistakes like trailing commas, single quotes, and unquoted keys.
Validation follows the strict JSON standard (RFC 8259) and runs as you type.
JSON validator FAQs
Is JSON validator free?
JSON validator is a free online tool on ReallyUseful.Tools. No account is required.
Does JSON validator run in my browser?
JSON validator is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.
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