Hex to Decimal
Type a hexadecimal number below to get the decimal value — other bases are shown too. The manual method is explained further down.
Try it
Custom base
Two’s complement
How to convert by hand
Multiply each digit by 16 raised to its position, counting from 0 on the right:
FF = F×16^1 + F×16^0
= 15×16 + 15×1
= 255
Reference table
Hex → Decimal
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
A 10
B 11
C 12
D 13
E 14
F 15
10 16
20 32
40 64
64 100
7F 127
80 128
FF 255
100 256
3E8 1000
400 1024
1000 4096
FFFF 65535
In code
JavaScript
parseInt('FF', 16) // 255Python
int('FF', 16) # 255