The Waite Group's C++ Primer Plus, Third Edition

Binary and Hex

Hex notation often is used to provide a more convenient view of binary data, such as memory addresses or integers holding bit-flag settings. The reason is that each hexadecimal digit corresponds to a four-bit unit. Table A.2 shows this correspondence.

Table A.2. Hexadecimal digits and binary equivalents.

Hexadecimal digits	Binary equivalent	Hexadecimal digits	Binary equivalent
0	0000	8	1000
1	0001	9	1001
2	0010	A	1010
3	0011	B	1011
4	0100	C	1100
5	0101	D	1101
6	0110	E	1110
7	0111	F	1111

To convert a hex value to binary, just replace each hex digit by the corresponding binary equivalent. For example, the hex number 0xA4 corresponds to binary 1010 0100. Similarly, you easily can convert binary values to hex notation by converting each 4-bit unit into the equivalent ...