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

Try another value

Edit this value or switch its base. Your changes are calculated in your browser with exact integer arithmetic.

Input base:
Decimal128
Hex0x80
Binary0b10000000
Octal0o200

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

This tool runs entirely in your browser - nothing you enter is uploaded or stored.

Want to learn the method behind this tool? Read How to Convert Binary to Decimal - the full step-by-step guide.