Type or pick a color and copy it in any format.
The converter accepts HEX in 3, 4, 6 or 8 digits, RGB and RGBA, HSL and HSLA, and standard CSS color names, and shows the same color in every other format. Alpha is preserved where it makes sense.
The contrast panel measures the color against white and black text using the WCAG formula and labels the result AA, AAA or fail, which helps you choose readable text on a colored background.
It is a mathematical conversion. Real print results depend on the printer, paper and color profile, so use it as an approximation.
WCAG asks for at least 4.5 to 1 for normal text and 3 to 1 for large text at level AA. Level AAA asks for 7 to 1 for normal text.
Yes, any standard CSS color name such as tomato or rebeccapurple.