What is Decimal?

Decimal is our everyday number system. It uses ten digits: 0 to 9.

What is Binary?

Binary is a number system that uses only two digits 0 and 1. Computers use binary to process data.

How to Convert Decimal to Binary

To change a decimal number to binary:

  1. Divide the number by 2
  2. Keep track of the remainder (0 or 1)
  3. Divide the result by 2 again
  4. Repeat until you get 0
  5. Read the remainders from bottom to top

Step by Step Example How to Convert 13 to Binary

Division Result Remainder
13 ÷ 2 = 6 6 1
6 ÷ 2 = 3 3 0
3 ÷ 2 = 1 1 1
1 ÷ 2 = 0 0 1

Reading the remainders from bottom to top: 13 in decimal = 1101 in binary

Conversion Table

Decimal Binary Explanation
0 0000 Zero in both systems
1 0001 Smallest positive number
2 0010 2^1
3 0011 2^1 + 2^0
4 0100 2^2
5 0101 2^2 + 2^0
6 0110 2^2 + 2^1
7 0111 2^2 + 2^1 + 2^0
8 1000 2^3
9 1001 2^3 + 2^0
10 1010 2^3 + 2^1
11 1011 2^3 + 2^1 + 2^0
12 1100 2^3 + 2^2
13 1101 2^3 + 2^2 + 2^0
14 1110 2^3 + 2^2 + 2^1
15 1111 2^3 + 2^2 + 2^1 + 2^0