between 8-12% of all men are colorblind. Very, very few women are (
IIRC, the genes lie in the X and Y chromosomes, and men are missing a good chunk, which means that recessive color deficiencies express more easily).
http://www.biyee.net/v/color_vision_tes ... d_test.htm
You need to do 48+ of them to get a good reading, but they are very, very simple choose the closest color match type tests. Shouldn't take more than 2-3 minutes.
Note that the brightness of the color may be different - you're supposed to choose the same shade, not the same brightness.
Test Protanopia Deuteranopia Tritanopia
Adjusted Score (%) 72 76 100
-Adam