ScanSpotJSON Formatter
Format, validate and minify JSON instantly.
Syntax errors pinpointedPretty or minified outputUpload .json files too
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{} JSON Formatter
Format or minify JSON. Supports file upload.
Format messy JSON into readable, indented structure, or minify it back down for production. Invalid JSON is reported with the exact position where parsing failed.
How to use the JSON Formatter
- Paste or type your JSON into the input panel.
- Press Format to pretty-print it, or Minify to strip all whitespace.
- Copy the result. If the JSON is invalid, the error message points at the offset that broke parsing.
Why people use it
- Saves you hunting for a missing comma by eye — the validator tells you where parsing stopped.
- Two-space indentation by default, so diffs of the formatted output stay small and reviewable.
- Runs entirely client-side, so private API payloads and access tokens never leave your machine.
Frequently asked questions
What makes JSON invalid?
Trailing commas, single-quoted strings, unquoted keys, comments, and NaN or Infinity values. Standard JSON allows none of these, even though JavaScript object literals do.
Can it handle very large files?
Parsing happens in your browser, so a multi-megabyte document is limited by your device's memory rather than a server quota. Very large files may briefly freeze the tab.
Does it sort or rewrite my keys?
No. Key order and values are preserved exactly — only whitespace changes.