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CSS How to Make a Website Customizing Colors and Fonts Use Color in CSS

I need help understanding the Hexadecimal rule.

does each number represent a color? how does a programmer memorize all these complicated codes?

5 Answers

Clinton Hopgood
Clinton Hopgood
7,825 Points

Hex color codes are made up of 3 sets of 2 numbers. Each set representing Red, Green and Blue in that order


The spectrum goes as follows starting with black and ending is white.

1 2 3 4 5 6 7 8 9 A B C D E F

E.g. #111111 = black #ffffff = white

Semantically, #111111 is a shade of gray and and #000000 is technical black.


Each number represents a different colour. Hexadecimal is in Base 8 so if goes like this:

1 2 3 4 5 6 7 8 9 A B C D E F

Here is a good example:


Also no programmer memorises all of the different colour codes, I look them up on http://color.hailpixel.com/ or http://flatuicolors.com . I do however remember some of them off hand like #000 #FFF #CCC #F0F0F0.

I hope this helps!


Hexadecimal is base 16, Octal is base 8.

Smashing Magazine has an excellent piece on this.

As the article says, there are: 16,777,216 varieties of "color" when using Hex.

I just remember that 00 is the least amount of the corresponding Red Green or Blue and that FF is as much of that color as possible. A lot of Hex memorization just comes from using codes...basically osmosis.

You are most welcome!

Oh yeah sorry about that! I wondered why it went up to 16 __ :(.