Hexadecimal Numbers: Base 16
4 binary digits can be represented by 1 hex digit.
Hexadecimal Numbers: Base 16
4 binary digits can be represented by 1 hex digit.
Hexadecimal
If we write a large number as a binary number, it can be quite long.
The hexadecimal, (hex) base 16, is used because every 4 binary digits can be represented by one hexadecimal digit.
In binary, base 2, there are 2 digits: 0, 1.
In decimal, base 10, there are 10 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9.
In hexadecimal, base 16, there are 16 digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E, F.
The table below shows the corresponding values of decimal, binary, and hexadecimal:
Decimal |
Binary |
Hexadecimal |
0 |
0000 |
0 |
1 |
0001 |
1 |
2 |
0010 |
2 |
3 |
0011 |
3 |
4 |
0100 |
4 |
5 |
0101 |
5 |
6 |
0110 |
6 |
7 |
0111 |
7 |
8 |
1000 |
8 |
9 |
1001 |
9 |
10 |
1010 |
A |
11 |
1011 |
B |
12 |
1100 |
C |
13 |
1101 |
D |
14 |
1110 |
E |
15 |
1111 |
F |
To convert a binary number to hexadecimal, first break it into groups of 4 starting on the right. You can always add 0 on the left without changing the value of a number. If the left most group does not have 4 digits, just add zeroes on the left to make a group of 4. Then replace each group of 4 with the corresponding hexadecimal digit from the table above.
Example: Convert 10110111110112 to hexadecimal (base 16)
Break into groups of 4 starting on the RIGHT: 0001,0110,1111,1011
Write the hexadecimal digit for each group of 4:
0001,0110,1111,1011
1 6 F B
There we have it: 10110111110112 = 16FB16
The place values in hexadecimal start with the ones place on the right, then multiply by 16 for each place moving to the left:
1,048,576 |
65,536 |
4096 |
256 |
16 |
1 |
165 |
164 |
163 |
162 |
161 |
160 |
The hexadecimal number 16FB is shown below with the place values:
The decimal value is 1x4096 + 6x256 + 15x16 + 11x1.
Or: 4096 + 1536 + 240 +11, which is 5883.
Fortunately, we don't usually have to convert hexadecimal to decimal.