JSON Formatter & Validator
Format, beautify, minify and validate JSON online. Shows exact error positions and sorts keys. Private and offline.
How to use JSON Formatter & Validator
- Paste your JSON.
- Choose Format or Minify and the indentation.
- Fix any errors shown, then copy or download.
Frequently asked questions
Is my JSON sent to a server?
No. Parsing uses your browser’s built-in JSON engine.
Why is my JSON invalid?
Common causes are trailing commas, single quotes and unquoted keys. The error message shows the line and column.
Is JSON Formatter & Validator free?
Yes. JSON Formatter & Validator is completely free, with no sign-up, no watermark and no usage limits.
Is my data uploaded to a server?
No. JSON Formatter & Validator runs entirely in your browser. Your files and text never leave your device.
Does it work offline?
Yes. After Red Cat Tools has loaded once, this tool keeps working without an internet connection. You can also install Red Cat Tools as an app.
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