Hex codes are especially useful for matching colors in an Illustrator document to those on a Web page, as both HTML and CSS use hexadecimal codes to specify colors.

I’ll note that Charity’s star color page has a hex code for the color of planetary nebulae, and that’s a whole nuther can o’ worms. Advertisement. Advertisement. Advertisement.

This list of Color Picker freeware tools and free online web services will help you identify HTML color HEX, RGD, etc codes from images, websites, etc. Free Color Code Finder software for Windows PC.