In a signed binary, the first bit (the leftmost) is reserved for the sign,
1 = negative, 0 = positive. This bit does not count when calculating the absolute value.
2. Construct the unsigned binary number.
Exclude the first bit (the leftmost), that is reserved for the sign:
1000 0001 0000 0000 = 000 0001 0000 0000
3. Map the unsigned binary number's digits versus the corresponding powers of 2 that their place value represent:
214
0 213
0 212
0 211
0 210
0 29
0 28
1 27
0 26
0 25
0 24
0 23
0 22
0 21
0 20
0
The number 1000 0001 0000 0000(2) converted from a signed binary (base two) and written as an integer in decimal system (base ten):
1000 0001 0000 0000(2) = -256(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.