Web Design in a Nutshell, 3rd Edition

Converting decimal to hexadecimal

You can calculate hex values in the 0 to 255 range by dividing a number by 16 to get the first digit, then using the remainder for the second digit. For example, dividing the decimal number 203 by 16 yields 12 with a remainder of 11. The hexadecimal value of 12 is C; the hex value of 11 is B. Therefore, the hexadecimal equivalent of 203 is CB.

Fortunately, there are simpler methods for converting numbers to hexadecimal:

• Use a hexadecimal calculator. Windows users can find a hexadecimal calculator in the “Scientific” view of the Windows standard calculator. Mac users with OS X 10.4 (Tiger) can download the free Hex Calculator Widget at http://www.apple.com/downloads/dashboard/calculate_convert/hexcalculatorwidget.html.

• Use Table D-1, which translates decimal values from 0 to 255.

Table D-1. Decimal to hexadecimal equivalents

dec = hex	dec = hex	dec = hex	dec = hex	dec = hex	dec = hex
0 = 00	43 = 2B	86 = 56	129 = 81	172 = AC	215 = D7
1 = 01	44 = 2C	87 = 57	130 = 82	173 = AD	216 = D8
2 = 02	45 = 2D	88 = 58	131 = 83	174 = AE	217 = D9
3 = 03	46 = 2E	89 = 59	132 = 84	175 = AF	218 = DA
4 = 04	47 = 2F	90 = 5A	133 = 85	176 = B0	219 = DB
5 = 05	48 = 30	91 = 5B	134 = 86	177 = B1	220 = DC
6 = 06	49 = 31	92 = 5C	135 = 87	178 = B2	221 = DD
7 = 07	50 = 32	93 = 5D	136 = 88	179 = B3	222 = DE
8 = 08	51 = 33	94 = 5E	137 = 89	180 = B4	223 = DF
9 = 09	52 = 34	95 = 5F	138 = 8A	181 = B5	224 = E0
10 = 0A