BaseShift

Number Base Converter

Edit any field — the other three update live. Great for programmers, students, and anyone debugging bitwise math.

Binarybase 2Octalbase 8Decimalbase 10Hexadecimalbase 16

Supports unsigned non-negative integers. Decimal value: 255.

What you entered

Decimal: 255

1
Decimal value
n = 255= 255
2
Convert to binary (base 2)
repeated division by 2, read remainders bottom-up= 11111111
3
Convert to octal (base 8)
repeated division by 8= 377
4
Convert to hexadecimal (base 16)
repeated division by 16= FF

Result

Binary: 11111111

255 in decimal is 11111111 in binary, 377 in octal, and FF in hexadecimal.

Numbers in binary, octal, decimal and hexadecimal

The same value written in base 2, 8, 10 and 16. Hexadecimal uses A to F for the values 10 to 15.

Decimal	Binary	Octal	Hexadecimal
10	1010	12	A
42	101010	52	2A
100	1100100	144	64
255	11111111	377	FF
1024	10000000000	2000	400
4095	111111111111	7777	FFF

255 as FF and 4095 as FFF are the rows worth recognising: hexadecimal maps exactly four binary digits to one hex digit, so 8 bits is always two hex characters and 12 bits always three. That is why colours are written as six hex digits - two each for red, green and blue, each covering 0 to 255. Octal groups three bits instead, which is why Unix file permissions use it: rwx maps neatly onto one octal digit. Binary grows fastest in length, which is precisely why hex exists as a compact way to write it.

Why hex is everywhere in code

Each hex digit (0–F) represents exactly 4 bits, so 1 byte fits in 2 hex digits and a 32-bit word in 8. That makes binary memory and colour values readable at a glance.

Frequently asked questions

What is 255 in binary and hexadecimal?

Binary: 11111111 (eight 1s — all bits set in a byte). Hex: FF. This is the maximum value of an unsigned 8-bit byte, which is why RGB color values max out at 255 and why hex colors go up to FF per channel.

How do I read a hex color like #3A7BF2?

Split it into pairs: 3A (red = 58), 7B (green = 123), F2 (blue = 242). Each pair is a hex byte (00–FF = 0–255). This color is a medium blue with low red, moderate green, and high blue. The color converter shows the RGB and HSL equivalents live.

Why do computers use binary instead of decimal?

Electronic switches have two reliable states: on (1) and off (0). Building circuits that distinguish 10 voltage levels (for decimal) is far harder and more error-prone than distinguishing just 2. Binary is less human-readable but vastly more reliable for hardware.