Note: You may have to turn your phone sideways or run this app on a computer.

Having recently played in a gym with tan walls, tan floors, and the lines were various colors mixed with lines for other sports, and playing with orange balls, I noticed that some of the players had quite a bit of difficulty seeing what they were doing. This was evidenced in what appeared to be late reaction time. Another effect was noticed when players would sometimes watch a ball land in bounds, say “Out!” and then sheepishly admit that it was actually in bounds. Could colorblindness have been a factor? Might it be a factor for you? Find out with the little app above. The repair is easy: Just ask everyone to switch to a different color ball. Chances are, you’ll find others will appreciate the change also, since approximately 12% of men are colorblind. Although fewer, millions of women are also affected.


You can run this program to find out whether you are colorblind. And if you are colorblind, you can play with this a few minutes a day as an exercise to discern colors better.

The colors will start to change as random words appear. Ideally, you will always be able to read a word although it may be very faint at times. If a word disappears entirely, you can click the Back button to look again at the color combination that’s hard to see. You can click the Speed button to slow the program down, and you can click the Step buttons to check one step at a time.

Before assuming you are colorblind, move up and down and from side to side in case your screen is harder to see at some angles. You may also want to try it on another computer.

If you still can’t see a word, you might want to note the Red, Green and Blue values of the foreground and background. You may be blind to these color combinations.

This is presented as fun, not a medically proven technique. But it may help. With practice and patience many people have overcome seemmingly impossible obstacles. This program is not intended as a replacement for proper eye care.