Really, this is just an excuse to post the following link: Psychology of Color – Helpscout. How to (not) learn how to use color. Notes after the break …
As a designer/artist, I have always found color to be one of the most important and most difficult parts of any new design. I would often look for help in finding the perfect color combinations and inspiration for logos, corporate design, etc. But in the end there is no true guide. So when I would read claims like those mentioned in the linked article, I would always feel less certain about what color choices to make.
Really, you should just go read the article. If you are working with design, web, or branding, it gives some nice insight into what color can’t and doesn’t do. I would even take the findings listed, even though they are research based, with a large grain of salt. But there is one specific point I want to reiterate here:
Color vs. Contrast
This is very well documented in the article, but I have heard it far too often. There is no specific color that will boost your sales. Particularly with Call-to-Action buttons. I recently was party to (but did not take part in) a complete redesign of a company website. One thing said stuck out in my mind:
“We made the call-to-action button green, because green is supposed to have the highest conversion rate.”
As the article explains very well—Contrast, not color, is the determining factor. Color is extremely important in this sense, but it is not a specific color that makes a button covert more, it is a specific color in context with its surroundings.