Also referred to as related colors, these are the colors directly on the left and right of your key color. They usually match up quite well and create a serene and comfortable design. While this color harmony can be pleasing to the eye, it can also come across as monotone. If you are going for a design that’s primarily one color, this is a good choice.
Tips & Tricks: Don’t go more than about one and half colors away from your key color as that stretches color harmony and will start to look more like a triadic or tetradic harmony.