NCS es el acrónimo de Natural Color System (NCS), el sistema de color más utilizado por los profesinales de la pintura industrial.
Fue desarrollado por el Instituto Escandinavo del Color en 1960 y se basa en los estudios elaborados por Hering, que redujo todos los colores visibles a la mezcla de cuatro únicos tonos: amarillo, rojo, verde y azul más blanco y negro.

A partir de las mezclas de colores entre sí y con el blanco y el negro que se van incrementando en un 10% de intensidad, se derivan 13 escalas de color que se consideran un estándar internacional desde 1976.

Debido a los diferentes calibrados de pantalla, la apreciación de los colores puede variar de un equipo a otro, por lo que esta tabla es solamente orientativa.

The Natural Color System (NCS) is a proprietary perceptual color model published by the Scandinavian Colour Institute (Skandinaviska Färginstitutet AB) of Stockholm, Sweden. It is based on the color opponency description of color vision, first proposed by German physiologist Ewald Hering. The system is usually used for matching colors (using printed reference cards), rather than mixing colors.

The underlying physiological mechanisms involved in color opponency include the bipolar and ganglion cells in the retina, which process the signal originated by the retinal cones before it is sent to the brain. A model like RGB describes what happens at the lower, retinal cone level, and thus is very well fitted for the task of "fooling the eye" as done by TV sets and computer displays. The NCS model, for its part, describes the organization of the color sensations as perceived at the upper, brain level, and thus is much better fitted than RGB to deal with how humans experience and describe their color sensations (hence the "natural" part of its name); but it would be useless, for example, for describing the behaviour of mixing lights and pigments.