Home / Text & data tools / JSON Formatter
JSON formatter & validator
Paste messy JSON, get it pretty — or minified — with precise error messages when something's broken.
Runs locally — JSON with keys, tokens or customer data never leaves your device.
How to format JSON
- Paste your JSON (or load a .json file).
- Click Format — choose 2 spaces, 4 spaces or tabs. Or click Minify to compact it.
- Copy or download the result. Errors show the exact line and position.
Frequently asked questions
Is my JSON sent anywhere?
No — everything runs locally. That matters because JSON often contains API keys, tokens and customer data.
Why is my JSON invalid?
The most common culprits: trailing commas, single quotes instead of double quotes, unquoted keys, and comments (JSON doesn't allow them). The error message points at the exact position.
Does it handle big files?
Yes — multi-megabyte JSON formats fine. For very large files, minify view is faster to render than pretty-print.