128 in Binary
Decimal 128 equals 10000000 in binary.
Why this number matters: 128 is 2⁷ - the sign bit of an 8-bit integer. As a signed byte it wraps around to -128.
128 in all number bases
Decimal128
Hexadecimal0x80
Binary1000 0000
Octal200
Try another value
Edit this value or switch its base. Your changes are calculated in your browser with exact integer arithmetic.
Input base:
Decimal
128Hex
0x80Binary
0b10000000Octal
0o200How 128 converts from decimal to binary
Divide by 2 repeatedly and keep each remainder, then read the remainders from bottom to top:
128÷ 2 =64remainder0
64÷ 2 =32remainder0
32÷ 2 =16remainder0
16÷ 2 =8remainder0
8÷ 2 =4remainder0
4÷ 2 =2remainder0
2÷ 2 =1remainder0
1÷ 2 =0remainder1
Result (remainders bottom to top): 10000000
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