Why is the complementary color of RED (255;0;0) is 255;94;0?
The opposite color mixed with original are grey. This means
complementary color of RED (255;0;0) is 0;255;255.
You can use Photoshop to mix that colors and see the result.
(overlay with 50% opacity)
Or "kuler" wheel have other idea of the hues logical
What you're noticing is this:
The kuler wheel emulates an RYB (red-yellow-blue) color
model--even though, just like Photoshop, it's based on a RGB
system. This shifts all the complementary hues (e.g., instead of
red-cyan, the complement pair is red-green).
The same color model is used in Illustrators color guide. I,
too, would love to know why this choice was made.