Color picker & converter
Pick a color and convert between HEX, RGB, HSL, HSV, and CMYK. See tints, shades, and contrast ratios against black and white.
JSON formatter & validator
Format, beautify, validate, and minify JSON online. Pinpoint syntax errors by line and column, sort keys, and copy or download the result.
How to use JSON formatter & validator
Paste JSON to format, validate, or minify it instantly. Invalid JSON is flagged with the exact line and column of the error so you can fix it fast. Everything runs in your browser — API responses, config files, and tokens never leave your device.
What you can do
- Beautify with 2 spaces, 4 spaces, or tabs
- Minify to a single line for payloads and storage
- Sort keys alphabetically for stable diffs
- Validate and see the number of keys, arrays, and nesting depth
Tip: you can also drop a .json file onto the input box.
JSON formatter & validator FAQs
Is JSON formatter & validator free?
JSON formatter & validator is a free online tool on ReallyUseful.Tools. No account is required.
Does JSON formatter & validator run in my browser?
JSON formatter & validator is designed to run in your browser where supported, so files can stay on your device instead of being uploaded to a server.
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