Color Contrast Analysis
Color contrast is an often overlooked aspect of web accessibility evaluations. Ensuring sufficient color contrast allows for greater participation from individuals who may have differences in how they view and see colors. There are two color contrast tools that can help provide an indication as to whether or not the desired colors provide sufficient color contrast.
Colour Contrast Analyser
The Color Contrast Tool is a free desktop application (Win/OS X) in which you can select foreground and background colors and evaluate the level of contrast between them. This tool can be helpful in selecting colors during the development and design process.
WCAG Contrast Checker
A second tool is the WCAG Contrast Checker that is a Firefox extension and useful for when evaluating color contrast from within the browser. The WCAG Contrast Checker will identify potential color contrast issues throughout the website and offer simulations for different color-blindness conditions as well (red-blind, blue-blind, etc.).