What is a complementary color scheme?

A complementary color scheme is made up of colors that are opposite each other on the color wheel. The primary complementary color schemes are red with green, blue with orange and yellow with purple.

When a color wheel is not available for reference, complementary colors can be calculated with the basic knowledge of the three primary colors; red, blue and yellow. Each primary color's complement is the mixture of the other two primary colors, also known as a secondary color. Complementary colors appear brighter and more vivid when placed next to each other. However, mixing complementary colors results in a brown color.