JSON Formatter & Validator
Format and beautify JSON with custom spacing and clear error reporting. Paste it in or upload a file.
The formatted JSON appears here.
How to use it
- 01
Add your JSON
Paste it in, or upload a .json file.
- 02
Choose your spacing
1 to 4 spaces, or compact to minify.
- 03
Click Format JSON
Any syntax error is shown with its position.
- 04
Copy or download
Take the formatted result with you.
JSON questions
Why is my JSON invalid?
The usual causes are a trailing comma after the last item, single quotes instead of double quotes, unquoted keys, or comments — none of which are allowed in standard JSON.
What spacing options are there?
Indent with 1 to 4 spaces, or choose Compact to minify. Four spaces is easiest to read; compact is best for production.
Is my JSON sent to your server?
No. The formatter runs entirely in your browser, so your data never leaves your device.
Can I format large files?
Yes, within reason. Because everything runs in your browser, very large files depend on your device's memory and speed.