# Converting from binary to hexadecimal

Convert $66.25$ to hexadecimal

I am finding it easier to convert from binary to hexadecimal so I start with writing it in binary which is: $1000010.01$ now to convert to hexadecimal we take each $4$ bits and sum it, but what about the numbers to the right of the radix point?

• You do the same, leading to the grouping $(0100)(0010){.}(0100)$. – Lutz Lehmann Dec 30 '16 at 12:50
• However, $66.25=42.4_{16}$. – Bernard Dec 30 '16 at 13:00

...what about the numbers to the right of the radix point?

You simply group them into groups of four digits, just the same as you will group digits to the left of the radix point, and translate each group of four binary digits into a single hexadecimal digit.

With digits to the left, you include leading zeroes as necessary to complete the groupings of four digits. With digits to the right, include trailing zeroes as necessary.

I'll work a different problem, leaving your particular example ($66.25$) for you to do yourself:

$87.375$

In binary:

$1010111.011$

With groupings of four binary digits each:

$(0101)(0111).(0110)$

$57.6$