HEX Color Validator
Validate one HEX color value locally. Supported forms are #RGB, #RGBA, #RRGGBB, and #RRGGBBAA.
Enter one value up to 100 characters. This checks syntax only.
A QUICK WALKTHROUGH
How to use this tool
- Enter one HEX color value.
- Choose Validate.
- Review the supported form and normalized uppercase value.
Explicit syntax only
The validator accepts #RGB and #RRGGBB, plus the optional-alpha forms #RGBA and #RRGGBBAA. The leading # is required and hexadecimal digits are case-insensitive.
Syntax scope
This checks only the bounded HEX color syntax described above. It does not assess accessibility contrast, named colors, CSS declarations, gradients, or other CSS color functions.
Local and bounded
Validation happens in your browser and the input is limited to 100 characters. No value is uploaded or stored.
GOOD TO KNOW
Common questions
Are alpha forms supported?
Yes. Four-digit #RGBA and eight-digit #RRGGBBAA values are accepted.
Is a 0x prefix accepted?
No. Use a leading #, such as #336699.
Does valid mean accessible?
No. This tool reports syntax only; check contrast and other design requirements separately.