What is the complementary color of red?

The complementary color of red in pigment is yellow+blue = green.

The red complementary color in the spectrum is green+blue = cyan.

complementary colour

The complementary colors in colors are red and green, blue and orange, purple and yellow. In optics, when two colors of light are mixed together in a proper proportion to produce a white feeling, the two colors are called "complementary colors".

Optical complementarity

Equal amount of red light+green light = yellow light, which is complementary to blue light;

Equal amount of red light+blue light = magenta light (also called magenta, that is, light purple), which is complementary to green light;

Equal amount of green light+blue light = green light, which is complementary to red light.

If one of the three primary colors is equal to other colors to form white light, these two colors are called complementary colors. Complementary colors can block each other. So we can know the following three pairs of complementary colors: yellow and blue, red and cyan, green and magenta.

Complementary colors in colors will reduce color purity and turn gray. Generally, you don't need complementary colors when painting.

However, when the two colors are complementary to each other, when one color occupies a much larger area than the other, the contrast of the picture can be enhanced and the picture can be eye-catching. Generally speaking, the use of complementary colors has advantages and disadvantages.