**Hex color code** (hexadecimal notation) is a very common format for representing colors in the RGB color palette. It is used in HTML, CSS and graphics programs, among others.

## Hex color code notation

The color hexadecimal notation consists of six hexadecimal digits - #123ABC. Each hexadecimal digit can take values from 0 to 15, where digits represent values from 0 to 9 and letters:

A – 10,

B – 11,

C – 12,

D – 13,

E – 14,

F – 15.

The six hexadecimal digits form three bytes that represent the colors red, green, and blue according to the RGB model. Each byte consists of two hexadecimal digits and can take a value from 00 (0) to FF (255).

We can shorten the notation only if each byte consists of two identical digits, for example:

The fuchsia color (#FF00FF) can be written as #F0F.

## Converting hex color code to RGB values

To get an RGB value in the range of 0 to 255, you must for each byte:

• Multiply the first hexadecimal digit by 16

• Read the value of the second digit

• Sum the two numbers

For the example, we will use the beautiful green color #6DC415.

Initially, we need to split the hex code into three bytes representing each of the RGB colors: # 6D | C4 | 15.

First byte 6D (Red):

6 -> 6 × 16 = 96

D -> 13

Red color -> 96 + 13 = 109

Second byte C4 (Green):

C -> 12 × 16 = 192

4 -> 4

Green color -> 192 + 4 = 196

Third byte 15 (Blue):

1 -> 1 × 16

5 -> 5

Blue color -> 16 + 5 = 21

To sum up:

**#6DC415 => red: 109, green: 196, blue: 21.**

## How many colors can we represent in hex codes?

Since each byte can be represented by 256 values (from 0 to 255) in hexadecimal we can write down 256 × 256 × 256 colors, for a total of **16,777,216**. Interestingly, hexadecimal notation that takes into account transparency in the format #AARRGGBB, where AA stands for 'Alpha', or transparency (FF = 100%, 00 = 0% transparency), is becoming popular. In this case, the number of colors is 256 × 256 × 256 × 256, for a total of 4,294,967,296.

### Example of hex codes in the HTML color palette:

Red = #FF0000 = RGB(255, 0, 0)

Green = #008000 = RGB(1, 128, 0)

Blue = #0000FF = RGB(0, 0, 255)

White = #FFFFFF = RGB(255,255,255)

Black = #000000 = RGB(0,0,0)

## Example of using hex code in HTML and CSS

On each example, you will get the same red background color:

- Hex: <div style=”background-color:#FF0000″></div>
- RGB: <div style=”background-color:rgb(255, 0, 0)”></div>
- Name: <div style=”background-color:red”></div>

Note that the name can only be used in more than 100 of the 16,777,216 colors.