Which format to use where
HEX (#1f7a58) is the standard on the web and in design tools. RGB is used in CSS and code. HSL (hue, saturation, lightness) is the easiest to adjust by hand — change the lightness to get lighter or darker versions. CMYK is for print.
Accepted inputs
Paste HEX (3 or 6 digits), rgb() and rgba(), hsl() and hsla(), or any CSS color name such as teal or tomato. All other formats update at once.