COLOUR HEX VALUES

What are Hex values and what do they mean?

It's quite simple really. A computer monitor, like a TV has all the colours made by combining differing amounts of the three primary colours,

RED - GREEN - BLUE

The digits contained in the Colour Hex Value correspond to those colours

33 - 66 - 99
Hex is short for Hexadecimal which is a numbering system with a base of 16 unlike Decimal which has a base of ten. What this means is if you start counting from 01, 02, 03 etc. you go past 10 to 16 before the first digit changes to a 1. As there are only ten number symbols 0,1,2,3,4,5,6,7,8,9 we have to use the first six letters of the alphabet to get to 16. So counting to 16 in Hexadecimal looks like this:

1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F, 10 and continues on as follows:

11, 12, 13, 14, 15, 16, 17, 18, 19, 1A, 1B, 1C, 1D, 1E, 1F, 20

Confused? Well I am! The reason we use Hexadecimal is because computers use it. Luckily we don't have to do any maths with it we just have to have a very basic knowledge of what's going on.

Most browsers support what are called 'Websafe' colours. This means we only use certain values of each colour. These are as follows:

00 33 66 99 CC FF
           

Because we are mixing light and not paint, the more we increase the 'Hex' value the brighter the colour gets. These leads to some unusual and often unexpected results.
In the table above we are going from 00 which is 0% RED to FF which is 100% RED.
The hex values of the GREEN and BLUE are both 00 so the final hex value of pure 100% RED is shown as

FF 00 00

If it's making sense so far we'll carry on.
Early computer could only display 16 colours made up from 0% (00), 50% (99) and 100% (FF) of each of the primary colours. The available colours were as follows:

FFFFFF 000000 FF0000 00FF00 0000FF 00FFFF FFFF00 FF00FF
               
999999 000099 009900 990000 990099 999900 009999 FF9900
               

With the development of SVGA monitors came the ability to show 256 colours on the screen. This was then the basis of the 'websafe' colour system which basically has 216 colours. These are displayed in the table below:

  FFFFFF   FFFFCC   FFFF99   FFFF66   FFFF33   FFFF00
  FFCCFF   FFCCCC   FFCC99   FFCC966   FFCC33   FFCC00
  CCFFFF   CCFFCC   CCFF99   CCFF66   CCFF33   CCFF00
  CCCCFF   CCCCCC   CCCC99   CCCC66   CCCC33   CCCC00
  CC99FF   CC99CC   CC9999   CC9966   CC9933   CC9900
  99CCFF   99CCCC   99CC99   99CC66   99CC33   99CC00
  9999FF   9999CC   999999   999966   999933   999900
  9966FF   9966CC   996699   996666   996633   996600
  6699FF   6699CC   669999   669966   669933   669900
  6666FF   6666CC   666699   666666   666633   666600
  6633FF   6633CC   663399   663366   663333   663300
  3366FF   3366CC   336699   336666   336633   336600
  3333FF   3333CC   333399   333366   333333   333300
  3300FF   3300CC   330099   330066   330033   330000
  0033FF   0033CC   003399   003366   003333   003300
  0000FF   0000CC   000099   000066   000033   000000
  FF99FF   FF99CC   FF9999   FF9966   FF9933   FF9900
  99FFFF   99FFCC   99FF99   99FF66   99FF33   99FF00
  FF66FF   FF66CC   FF6699   FF6666   FF6633   FF6600
  66FFFF   66FFCC   66FF99   66FF66   66FF33   66FF00
  FF33FF   FF33CC   FF3399   FF3366   FF3333   FF3300
  33FFFF   33FFCC   33FF99   33FF66   33FF33   33FF00
  FF00FF   FF00CC   FF0099   FF0066   FF0033   FF0000
  00FFFF   00FFCC   00FF99   00FF66   00FF33   00FF00
  CC66FF   CC66CC   CC6699   CC6666   CC6633   CC6600
  66CCFF   66CCCC   66CC99   66CC66   66CC33   66CC00
  CC33FF   CC33CC   CC3366   CC3366   CC3333   CC3300
  33CCFF   33CCCC   33CC99   33CC66   33CC33   33CC00
  CC00FF   CC00CC   CC0099   CC0066   CC0033   CC0000
  00CCFF   00CCCC   00CC99   00CC66   00CC33   00CC00
  9933FF   9933CC   993399   993366   993333   993300
  3399FF   3399CC   339999   339966   339933   339900
  9900FF   9900CC   990099   990066   990033   990000
  0099FF   0099CC   009999   009966   009933   009900
  6600FF   6600CC   660099   660066   660033   660000
  0066FF   0066CC   006699   006666   006633   006600

Browsers will now support more colours as Monitor and Graphics quality has improved. Most HTML editors also contain 'colour pickers' which automatically insert the Hex Value of any colour. If not separate programmes are available for this purpose. Many Image Editing programmes also contain palettes for chosing 'websafe' colours if required.

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