Technical Calculator

One's Complement Calculator

Add the number and click on the “Calculate” button to find its one’s (1’s) complement.

Input Format:

Decimal Number Range = -127 to 127

One's Complement Calculator

This 1’s complement calculator helps to find the complement of 1’s for the decimal, binary, or hex numbers system. Convert the numbers from these systems to their equivalent one complement by flipping all the bits i.e., 0’s to 1’s and 1’s to 0’s.

One’s Complement (Definition):

It’s a value that is calculated by inverting bits in the signed binary representation of the given number.

One's Complement Symbol:

One complement of a number is represented as ‘~’ which is also known as the bitwise operator.

How to Find One’s Complement?

You can calculate 1’s complement of a binary numeral by two methods:

2.1 Manual Calculations

  1. Convert the given number (decimal or hex) to its equivalent binary form
  2. Invert all the bits in the calculated binary number to find the one’s complement

2.2 Calculate Online

Access our “One’s Complement Calculator” and start calculation for 1’s complement frequently by only adding numbers.

Solved Examples (Ones Complement):

Example 01:

Find the binary to one’s complement representation for the given number:

\(\left(1010001010111\right)_{2}\)

Solution (step by step):

Step 01: Write the given number

\(\left(1010001010111\right)_{2}\)

Step 02: Find 1’s Complement

Invert all the bits in the number i.e., 0’s to 1’s and 1’s to 0’s

\(\left(1010001010111\right)_{2} = \left(0101110101000\right)_{2}\)

Example 02:

Calculate the 16-bit 1’s complement of the given number:

  • Decimal: 123

Solution:

Step 01:

Convert the given decimal number to the binary form

\(\dfrac{123}{2}\)

  • Sub-steps:
  • 123 ÷ 2 = 61, remainder 1
  • 61 ÷ 2 = 30, remainder 1
  • 30 ÷ 2 = 15, remainder 0
  • 15 ÷ 2 = 7, remainder 1
  • 7 ÷ 2 = 3, remainder 1
  • 3 ÷ 2 = 1, remainder 1
  • 1 ÷ 2 = 0, remainder 1

Step 02: Write all remainder starting from the bottom and ending at the top in the format “Left to Right”

\(\left(1111011\right)_{2}\)

Step 03: Find one’s complement

Flip all the bits in the above number

\(\left(1111011\right)_{2} = \left(0000100\right)_{2}\)

Step 04: Write the calculated complement value as a 16-bit representation

\(\left(0000 0000 0000 0100\right)_{2}\)

Example 03:

Convert the hexadecimal number ‘FA’ to 1’s complement notation:

Solution:

Step 01: Write the Binary Equivalent of the Given Numbers

\(F = \left(15\right)_{2} = \left(1111\right)_{2}\)

\(A = \left(10\right)_{2} = \left(1010\right)_{2}\)

Step 02: Invert All Bits to Find One’s Complement

\(\left(1010\right)_{2} = \left(0101\right)_{2}\)

One’s Complement Table:

Decimal, Binary, One's Complement, and Hexadecimal Equivalents
Decimal Binary 1's Complement Hexadecimal
1 0001 1110 1
2 0010 1101 2
3 0011 1100 3
4 0100 1011 4
5 0101 1010 5
6 0110 1001 6
7 0111 1000 7
8 1000 0111 8
9 1001 0110 9
10 1010 0101 A
11 1011 0100 B
12 1100 0011 C
13 1101 0010 D
14 1110 0001 E
15 1111 0000 F
16 10000 01111 10
17 10001 01110 11
18 10010 01101 12
19 10011 01100 13
20 10100 01011 14
21 10101 01010 15
22 10110 01001 16
23 10111 01000 17
24 11000 00111 18
25 11001 00110 19
26 11010 00101 1A
27 11011 00100 1B
28 11100 00011 1C
29 11101 00010 1D
30 11110 00001 1E
31 11111 00000 1F
32 100000 011111 20
33 100001 011110 21
34 100010 011101 22
35 100011 011100 23
36 100100 011011 24
37 100101 011010 25
38 100110 011001 26
39 100111 011000 27
40 101000 010111 28
41 101001 010110 29
42 101010 010101 2A
43 101011 010100 2B
44 101100 010011 2C
45 101101 010010 2D
46 101110 010001 2E

FAQs:

Why is it called 1’s complement?

When you add the 1’s complement to the original number, you get all 1’s. This is why it is called ones complement.

How to convert -52 (base 10) to binary 8-bit one's complement?

Step 01: Convert the given decimal number to binary: In binary system, 52 is written as

\(\left(110100\right)_{2}\), ignoring the negative sign.

Step 02: Find 1’s complement: Inverting all the bits,

\(\left(110100\right)_{2} = \left(001011\right)_{2}\)

In 8-bit representation, the above complement is given as:

\(\left(0000 1011\right)_{2}\)

What is the range of the ones complement?

One complement of a binary numeral can only be represented within the range

\(-\left(2^{\left(N-1\right)}\right)\) to \(\left(2^{\left(N-1\right)}\right)\).

What is the 1's complement of hexadecimal number B?

  • The hexadecimal number is equal to 11 when converted to decimal system
  • The binary equivalent of 11 is \(\left(1011\right)_{2}\)
  • One complement of \(\left(1011\right)_{2}\) is \(\left(0100\right)_{2}\)

Reference:

Wikipedia: Number representation, end-around borrow, Negative zero, Avoiding negative zero.

Geek For Geek: 1’s complement of a binary number, Addition of two negative numbers.

Tutorial Points: 1’s Complement of a Binary Number, Uses of 1’s Complement Binary Numbers, Range of Numbers, Additions by 1’s Complement.