Free online tool
JSON formatter & validator
Pretty-print or minify JSON and find mistakes, with the line and column of any error.
Works in your browserNothing is sent anywhereNo sign-upFree
Questions
Good to know
Is my text sent anywhere?
No. Everything happens in your browser on your own device. Nothing you type is sent to a server or saved.
Why is my JSON not valid?
Common mistakes: a comma after the last item, single quotes instead of double quotes, or keys without quotes.

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