About this tool
Paste JSON and get it neatly indented, or minified to a single line. If it is not valid, you get the parser's error message so you can find the problem. Because it runs entirely in your browser, it is safe to paste API responses or config you would not want to send to a random website.
How to use it
- 1 Paste your JSON into the input box.
- 2 Choose an indent size, or "Minify" to strip all whitespace.
- 3 Click "Format" - valid JSON is reformatted, invalid JSON shows the error.
- 4 Copy the result from the output box.
Frequently asked questions
Is my JSON sent to a server?
No. It is parsed and reformatted by your browser with the built-in JSON engine.
What does "minify" do?
It removes every space and line break, giving the smallest valid JSON - useful for embedding in code or config.
Why do I get an error on valid-looking JSON?
Common causes are trailing commas, single quotes instead of double, unquoted keys, or a stray character - the error message points to roughly where it stops parsing.
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