JSON formatter & validator
Pretty-print, minify and validate JSON with precise error positions.
Input
Output
Recent
Nothing here yet.
About this tool
Paste any JSON payload and get it back indented and readable, or collapsed into a single minified line. If the document is malformed, the tool reports what the parser expected and points at the line and column where it gave up — which is usually faster than re-reading the payload yourself.
Parsing happens with your browser's native JSON engine, so what you see here is exactly what your application would see. Nothing is uploaded: the payload never leaves the tab, which matters when the JSON you are debugging came from a production log.
How to use it
- 1Paste or type your JSON into the input panel.
- 2Choose an indentation width, or switch to minified output.
- 3Copy the formatted result, or read the error message if the document is invalid.
Privacy
This tool runs entirely in your browser. Nothing you type or paste is sent to a server, and your local history is stored only on this device.
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