"...two simple equations to determine if you should be using white or black text depending on the color of the background." from 24ways.

0to255 is a simple tool that helps web designers find variations of any color.

Analyse the color contrast of your web pages.

"Using contrast effectively not only differentiates our site's design from others, it’s the essential ingredient that can make our content accessible to every viewer, including the colorblind. By understanding contrast, we can create websites that unabashedly revel in color." from A List Apart.

from slayeroffice.

CSS3 introduces a couple of new ways to specify colours, and one of those is RGBA. The A stands for Alpha, which refers to the level of opacity of the colour, or to put it another way, the amount of transparency. from 24 ways.

Disable Photoshop’s color management for RGB documents as much as possible. from smashing magazine.

The color palette is shrinking.

The patterns and examples on this site help you create websites the color blind can use without problems.

how your final colors will appear on the web.

This page extracts the 12 most common colors from a photo on the web and provides a list of color references.

Colors come to life in 3D!

at the core of ui design lies logic and method. from the usability post.

from rww.

and three steps to color perfection.

from sitepoint blogs.

an online color scheme generator.

monitor color trends, compare color palettes.