JSON validator and formatter online
Validate, beautify, minify and sort JSON online. Shows the exact error line and column. Free, and your data never leaves your browser.
How it works
Paste your JSON and the tool validates it instantly (JSON lint). If there is an error, it shows the exact line and column and the snippet where the problem is: a trailing comma, a single quote or a missing bracket.
With one click you can pretty-print it with 2 or 4 spaces or tabs, minify it to send through an API or store it in less space, and sort keys alphabetically to compare two responses.
Frequently asked questions
Is my data sent to a server?
No. JSON is processed with JavaScript inside your browser, so you can safely use it with API responses or configs that contain sensitive data.
Why is my JSON invalid if it looks right?
The most common mistakes are trailing commas, single quotes instead of double quotes, unquoted keys and comments. JSON allows none of them.
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