JSON Formatter
Paste messy JSON and get clean, indented, valid output — with a clear error message if something is off.
Frequently asked questions
Does it validate my JSON?
Yes. If the input is invalid, it shows the parse error so you can fix it. Valid input is pretty-printed with 2-space indentation.
Can I change the indent size?
Use the indent control to switch between 2 and 4 spaces before formatting.
Is my data uploaded?
No. Parsing and formatting happen entirely in your browser.