Skip to content

10000000 in Decimal

Binary 10000000 equals 128 in decimal.

Why this number matters: 128 is 2⁷ - the sign bit of an 8-bit integer. As a signed byte it wraps around to -128.

10000000 in all number bases

Decimal128
Hexadecimal0x80
Binary1000 0000
Octal200

How 10000000 converts from binary to decimal

Multiply each digit by 2 raised to its position (starting at 0 from the right), then add the results:

1× 27 = 1 × 128 = 128
0× 26 = 0 × 64 = 0
0× 25 = 0 × 32 = 0
0× 24 = 0 × 16 = 0
0× 23 = 0 × 8 = 0
0× 22 = 0 × 4 = 0
0× 21 = 0 × 2 = 0
0× 20 = 0 × 1 = 0

Sum: 128