Two's Complement Calculator
Convert signed integers to two's complement binary and read signed binary back to decimal for any common bit width (4–64 bits or custom).
Two's complement is the standard signed integer representation: the most significant bit is 1 for negative values.
Pick 4, 8, 12, 16, 32, 64 bits, or a custom width from 2 to 64. Enter a decimal in the signed range or type binary (optional leading zeros).
The tool keeps decimal and binary in sync and shows the minimum and maximum value for your bit width.
Choose a bit width, then convert a signed integer to two’s complement binary or type binary to read it as signed decimal. Leading zeros in binary are optional; values are padded to the selected width.
Signed range for 8 bits: -128 … 127
Whole numbers from -128 through 127.
Up to 8 digits (0/1); spaces are ignored for counting. Result is shown in groups of four bits.
Quick checks
- : decimal 16 (8-bit)
- : signed binary 10111011 (needs ≥ 8 bits → −69)