Button color matters less than contrast

There's a recurring internet argument about whether red or green buttons convert better. The answer is neither. The button that converts best is the one that looks most different from everything around it.

If your page is mostly blue, an orange button pops. If your page is mostly green, a red button pops. It's not about the psychology of red meaning "stop" or green meaning "go." It's about visual hierarchy. The eye goes to the thing that doesn't match.

One test showed a red button beating a green button by 21%. On a mostly green page. Another showed green beating red by 14%. On a mostly red page. The winner was always the higher-contrast option.

This extends beyond buttons. Your most important element on any page should have the highest visual contrast. If everything is equally styled, nothing stands out, and the user has to figure out where to look. Don't make them figure it out.