For
some reason colors in HTML are specifyed using hexadecimal
numbers.
Hexadecimal numbers are numbers that
are based on the value of 16 rather than the classical numbers
based on the value of 10.
DECIMAL
vs. HEXADECIMAL NUMBERS
In classical numbers you have ten different
figures whereas in hexadecimal numbers you have 16 different
figures.
Below
is a table showing how to write the numbers from 1 to 20 in
both systems:
Decimal 
0 
1 
2 
3 
4 
5 
6 
7 
8 
9 
Hexadecimal 
0 
1 
2 
3 
4 
5 
6 
7 
8 
9 
Decimal 
10 
11 
12 
13 
14 
15 
16 
17 
18 
19 
Hexadecimal 
A 
B 
C 
D 
E 
F 
10 
11 
12 
13 
The
highest hexadecimal number you can specify using one figure
is F equalling 15.
With two figures the highest value is FF equalling 255.
Top
of page
RGBCOLORS:
Screencolors are generated from three
basic colors: Red, Green and Blue.
Therefore
it is helpfull to specify screencolors in a system based on
the amount of each of the three basic colors. Such a system
is called a RGBcolorsystem.
Most
graphic tools (photoshop, photopaint, paintshop pro etc.)
offers to handle colors in a RGBcolorsystem. To define a
certain color you simply enter the amount of each of the three
colors Red, Green and Blue.
The
same system is used in HTML.
Top
of page
HEXADECIMAL
VALUES IN HTML
A typical colordefinition in HTML
would look like this:
The
color is defined in the "#FF8C67".
The #
simply states that the following numbers are hexadecimal.
The first two digits are the amount of red.
Digit 3 and 4 specify the amount of green.
And finally digit 5 and 6 specify the desired amount of blue.
Below
is an example showing how different colors are mixed to obtain
the desired result:
Since
there are two hexadecimal figures for each color you can specify
256 gradients of each basic color. This gives a total of 256*256*256
= 16.777.216 different combinations.
However
not all of these colors will look the same on different browsers
and operating systems.
Top
of page
BROWSERSAFE
COLORS
Only
216 colors are, what we refer to as "browsersafe".
Browsersafe
colors are colors that looks the same no matter which browser
you see them on.
The
reason is that different browsers running on different platforms
interpret the colors differently. The only 216 colors that
looks the same no matter what, are the colors made out of
pairs of 00, 33, 66, 99, CC and FF.
An
example would be: "#990066".
You
should always strive to limit your use of colors to these
combinations. All colors that can be picked in the colorpicker
at the bottom of this screen are browsersafe.
Top
of page
CONVERTING
BETWEEN HEX AND DECIMAL VALUES
To calculate a hexadecimal value from
the decimal value do this:
 Enter
the decimal value in the calculator that comes as
a standardaddition in windows.

Click the Hexfield  and watch the calculator convert
the number to hex.

You
can of course go the other way around to calculate decimal
values from hex values.
NOTE:
If
you don't see the hexoption in the calculator, click the
viewmenu and choose scientific.
Top
of page
NAMED
COLORS
A few colors can be referred to using
names rather than hex values.
Below
is a listing of these colors and their names:

Black 


Yellow 


Red 


Maroon 

Gray 


Lime 


Green 


Olive 

Silver 


Aqua 


Blue 


Navy 

White 


Fuchsia 


Purple 


Teal 
Top
of page
COLORSAMPLES:
Below you see 15 tables covering the
entire rainbow.
All
colors in the table are browsersafe.
Use the tables to pick the hexadecimal
value of a desired color.
Each
table shows 36 different colorcombinations.
In the upper left corner of the table is the fixed amount
of either red, green or blue used for all samples in the table.
If the color of the upper left corner is red, for example,
it means that all samples in this table has a fixed amount
of red.
The fixed amount of this color is shown in the cell.
Depending
on which color is fixed for the table, the two other colors
can be read along the axis.
Or
simply click on the desired color to see the hexvalue.
Tell a friend about this site!!!
