Why is hexadecimal used in networking, and what are its 16 digits?
Hex (base 16) is used because one hex digit replaces four binary bits, making addresses far shorter to read; its digits are 0-9 then A-F (A-F = 10-15). It is used for IPv6 and MAC addresses.
Base 16 is the sweet spot for humans handling binary data: 16 = 2⁴, so one hex digit maps cleanly onto a 4-bit nibble with no leftover. That's why a 128-bit IPv6 address fits in just 32 hex digits and a 48-bit MAC address in 12 — far easier to read and copy than a wall of 0s and 1s. The only thing to learn is that the digits run past 9 into letters: A=10, B=11, C=12, D=13, E=14, F=15.
Hexadecimal (Base 16) is used because it's easier to read than long binary strings.
Common uses:
- IPv6 addresses
- MAC addresses (Ethernet)
- Memory addresses
The 16 hexadecimal digits:
| Decimal | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
|---|---|---|---|---|---|---|---|---|
| Hex | 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 |
| Decimal | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 |
|---|---|---|---|---|---|---|---|---|
| Hex | 8 | 9 | A | B | C | D | E | F |
Key: Letters A-F represent values 10-15.
Go deeper:
What is binary and hexadecimal? — a quick visual tour of counting past 9 into A-F and why hex packs binary tidily.
Wikipedia — Hexadecimal — base-16 digits, the nibble mapping, and why computing leans on it.