JSON Formatter
Format, validate, minify and explore JSON — handles huge inputs without freezing the tab.
Format, beautify, and validate JSON right in your browser. Paste messy or minified JSON and get clean, properly indented output, with syntax errors flagged so you can fix them fast. It is free, needs no signup, and everything runs on your device, so your data is never uploaded to a server.
How to use JSON Formatter
- Paste your JSON into the input box or type it directly.
- Choose your indentation (2 spaces, 4 spaces, or tabs) if the option is available.
- Click Format to beautify and validate the JSON.
- Review any errors that are highlighted and fix them.
- Copy the formatted result or clear the field to start again.
Frequently asked
Is the JSON formatter free?
Yes, it is completely free with no signup or account required.
Do you upload my JSON to a server?
No. All formatting and validation happens in your browser, so your data never leaves your device.
Can it validate JSON and show errors?
Yes. It checks your JSON as it formats and highlights syntax errors so you can find and fix them quickly.
Is there a size limit?
There is no fixed limit, but very large files depend on your browser and device memory since processing is local.
Can it minify JSON too?
It focuses on formatting and beautifying JSON with readable indentation; you can paste minified JSON to expand it.
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