Math Calculators

One's Complement Calculator

Find the one's complement of a non-negative integer for a given bit width — flipping every bit.

Original binary —

One's complement binary —

One's complement (decimal) —

About the One's Complement Calculator

The one's complement of a binary number is found by flipping every bit — every 0 becomes a 1 and every 1 becomes a 0. Within a fixed bit width, this is the same as subtracting the value from the all-ones maximum.

Formula: one's complement = (2^bits − 1) − value

One's complement was an early scheme for representing negative numbers in computing, later mostly replaced by two's complement, but it is still used in certain checksum algorithms.