Well, this number is probably much higher than you think. If you are truly looking to create a web accessible site, then you need to take color impaired visitors into consideration. For colorblind individuals, the wrong color combinations on a website can make navigation and interaction impossible.

‘‘A shocking 1 out of 12 visitors to any website are Colourblind to some degree.’’

I know what some of you might be thinking. Why should I create a website for a small group of people? You might be surprised to find out that colorblindness isn’t as rare as you think it is. This means that one in twelve of your visitors might be coming to your site with some sort of color disability. Just think how many visitors and customer conversions that you might lose if your website is not accessible and usable by the colorblind.

Heres a few benefits:

1. An accessible website is more likely to be ranked well with the search engines than an inaccessible website.
2. By designing a colorblind accessible website, you are also targeting PDAs, 3G phones, and similar technological devices that are used for web access.
3. It is seen as more professional to have a website that doesn’t exclude the impaired or disabled.
4. Equal access to everyone regardless of their abilities is always a nice things to do.

Unfortunately there isn’t only one kind of colorblindness to take into consideration when designing.

Trichromat Vision is the “normal” color vision, uses red/green/blue color receptors which is the kind of vision that most visitors have.

Now there are three different color vision impairments, and they are:

1. Anomalous Trichromat Vision
   Anomalous Trichromat vision, uses three color receptors but one pigment is misaligned
   • Protanomaly Vision: reduced color red sensitivity
   • Deuteranomaly Vision(most common): reduced color green sensitivity
   • Tritanomaly Vision: reduced color blue sensitivity
2. Dichromat Vision
   Dichromat vision, uses only 2 of the 3 visual pigments – red, green or blue is missing
   • Protanopia Vision: unable to receive color red.
   • Deuteranopia Vision: unable to receive color green.
   • Tritanopia Vision: unable to receive color blue.
3. Monochromat Vision (can see only one color)

As web designers, we are all used to having the entire palette of colors to choose from. Designing a website for the colorblind won’t limit your color palette at all, however, you will need to watch out for the color combinations that you do use. Learning what color combinations do not work, is a great place to start, because without this you will get nowhere. Basically, you need to remember to not use Red and Green Combinations, either to decipher link text, or images. Although most people see Red and Green as contrasting, those with Anomalous Trichromat Vision Colorblindness (the most common type) will not be able to tell these colors apart. This also applies to combinations with variations of green and red, including colors such as purple and orange.

‘‘Design contrast is important when designing for the colourblind.’’

It is necessary that you prioritize your website’s content to find the most important content. The more important the content, the more necessary that it will be to make these items colorblind-safe. The most important aspects of a website are usually navigational text (includes image and button text), menus, headers, and subheaders.

Make sure that these items are very high in contrast…this means that you should either make these items black and white or opposite ends of the color saturation pole to their particular over lying background colour. Black and white is the best possible contrasting scheme, but they do not offer much in the way of design, so a balance must be found

If you aren’t sure if a page is contrasted enough, one good tip is to desaturate your website (save first) in Fireworks or Adobe Photoshop and see if the images still have an impact. Desaturating the image will remove all the color from the image and this way you will be able to tell if the image has enough contrast without color to be seen.

Conclusion

Make sure when designing websites that you keep the visually impaired in mind, they have every bit a right to view the information on your site as anyone. If it means compromsing on that funky fade or sleak shade, then do it. Design can be found anywhere, and if lost in one place, can be made up in another.