How Color Codes Work

Normally, colors have names like blue or green or red, but when it comes to computer, they really have numbers, or codes. A color's code depends on what color it is and how much light/dark it has. This article talks about what goes into a color's code.

RGB

RGB stands for Red Green Blue. These 3 colors can be combined to make almost any other color. Different shades of each of the 3 colors are all that is needed to determine a color's code. For example, to a computer, if you wanted to represent the color blue, the R and G would be 0 and B would be 1. If you wanted to represent the color black, all three would be 0, representing something that is completely colorless. A color's code is determines by its RGB value.

Numeric/Decimal (0-255)

To represent different shades of the RGB colors, a number is assigned to each of the 3 colors. A number between 1-255 (the size of a byte) is used to represent the "amount" of that color to use. For example, if you wanted the final color to be red, the RGB would be: R=255, G=0, B=0. This would give us a completely red color.

Different combinations of numbers can be used with each color and the 256 possibilities for each to come up with almost any color/shade you want. For example, a color of R=120, G=120, B=120 would be a grayish color since all 3 numbers are equal. The higher the number, the lighter/brighter the color is, the lower, the darker the color is.

Hexadecimal

This is the most important concept to understand when reading a color's code. Computers understand colors as binary/hexadecimal. This is just a different numbering system than the Numeric from above. Basically instead of having one color go from 0-255 to represent the "amount" of the color in the color's code, rather you would use numbers between 0-FF. FF in hex is equivalent to 255 decimal. Often when you look at a color chart to find a color's code, it will be written in hex.

Usually 6 characters, something like "#FFA8F1" is used to represent a color. The "#" represents the fact that this is a hex number. The following 6 characters are the RGB value for the color's code (2 characters for each R, G, B). In this example, R=FF, G=A8, B=F1. That just tells the computer "how much" of each of the 3 colors to use to come up with the final color. This information in the color's code is what tells your computer what color you are wanting to use.

The most important thing to take away from this is that a computer creates the colors from different shades of Red, Green, and Blue. A color's code is often represented in hexadecimal as 6 characters where characters 1 and 2 are the Red, 3 and 4 are the Green, and 5 and 6 are the Blue part of the color's code as was seen in the above example.