Decimal to Hex
Type a decimal number below to get the hexadecimal 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
Divide by 16 repeatedly, note each remainder, then read the remainders from bottom to top:
255 ÷ 16 = 15 … F
15 ÷ 16 = 0 … F
→ FF
Reference table
Decimal → Hex
0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8
9 9
10 A
11 B
12 C
13 D
14 E
15 F
16 10
32 20
64 40
100 64
127 7F
128 80
255 FF
256 100
1000 3E8
1024 400
4096 1000
65535 FFFF
In code
JavaScript
(255).toString(16).toUpperCase() // 'FF'Python
format(255, 'X') # 'FF' (hex(255) → '0xff')