JSON Formatter & Validator
Format, check, and minify JSON, with the exact spot of any error.
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Your files stay on your device
How to use it
Paste your JSON to get it neatly formatted and checked instantly. If something’s wrong, you see the exact line and column. Your JSON stays on your device.
Paste your JSON into the box. If it’s valid, you get a neatly indented version ready to copy. If it’s not, you see exactly which line and column the problem is on — no hunting through a wall of text.
Turn on “Sort keys” to put every key in alphabetical order, which makes it easy to compare two JSON files that only differ in order.
Need it as small as possible for a request or a config file? Minify strips all the spaces and line breaks.
FAQ
Does this convert JSON to other formats?
No, it only formats and checks JSON. To convert, use JSON to CSV or CSV to JSON in the Data tools.
What does “sort keys” do to lists?
Nothing — list order stays exactly the same. Only object keys are sorted.
Can anyone else see my JSON?
No. It’s formatted on your device and never sent anywhere.
How it worksFor the curious
JSON is parsed and re-serialised with the browser’s native JSON.parse and JSON.stringify, so validation is exact: anything that parses here parses identically elsewhere.
JSON.parse only reports a character offset in its error. This tool converts that offset into a line and column by counting newlines in the input.
Sort keys reorders object keys alphabetically, recursively. Array order is never changed.