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:
1001 0001 0011 0111 = 001 0001 0011 0111
3. Map the unsigned binary number's digits versus the corresponding powers of 2 that their place value represent:
214
0 213
0 212
1 211
0 210
0 29
0 28
1 27
0 26
0 25
1 24
1 23
0 22
1 21
1 20
1
The number 1001 0001 0011 0111(2) converted from a signed binary (base two) and written as an integer in decimal system (base ten):
1001 0001 0011 0111(2) = -4 407(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.