How to convert a decimal number into binary? - step by step instruction

This post covers denary to binary conversion; point 1.1 in the Syllabus.

1. Draw an 8 column 2 row table.

 

2. Fill the first row with subsequent powers of 2, starting with 2^0, going from right to left.

3. Starting from the left, check if each power of 2 fits into your number - if it does, write down “1” in the second row, and subtract this given power of 2 from your number, and continue in the right direction.

Let’s analyse the process on the example of the number 57.

Now we rewrite the bottom row of our table into a string of numbers - 00111001 - which is our binary for 57! 

Try out converting different numbers from denary to binary (and the other way round too!). You can check your answers here.