A Hexadecimal Number is based on the number 16

## 16 Different Values

There are 16 Hexadecimal digits. They are the same as the decimal digits up to 9, but then there are the letters A, B, C, D, E and F in place of the decimal numbers 10 to 15:

 Hexadecimal: Decimal: 0 1 2 3 4 5 6 7 8 9 A B C D E F 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

So a single Hexadecimal digit can show 16 different values instead of the normal 10.

## Counting

Choose "Hexadecimal" below and watch it count:

After the "Units" position is filled up (when we reach F) the units start back at 0, and we add 1 to the next position on the left.

AFter that position reaches F, we do the same thing, and so on.

As we move left, every number place is 16 times bigger.

### Example: What is the decimal value of the hexadecimal number "D1CE"

= 53,248 + 256 + 192 + 14
= 53,710

## The Point !

### Example: 2E6.A3

This is 2×16×16 + 14×16 + 6 + 10/16 + 3/(16×16)
Read below to find out why

Numbers can be placed to the left or right of the point, to indicate values greater than one or less than one:

 The number just to the left of the point is a whole number, we call this place units. As we move left, every number place its 16 times bigger. The first digit on the right of the point means sixteenths (1/16). As we move further right, every number place its 16 times smaller (one sixteenth as big).

## More Examples

### Example 1: What is 2E6 (Hexadecimal)?

• The "2" is in the "16×16" position, so that means 2×16×16
• The "E" is in the "16" position, so that means 14×16
• The "6" is in the "Units" position so that means 6.
• Answer: 2E6 = 2×16×16 + 14×16 + 6 (=742 in Decimal)

### Example 2: What is 2.3 (Hexadecimal)?

• On the left side is "2", that is the whole number part.
• The 3 is in the "sixteenths" position, meaning "3 sixteenths", or 3/16
• So, 2.3 is "2 and 3 sixteenths" (=2.1875 in Decimal)

## The Word "Hexadecimal"

The word "Hexadecimal" means "based on 16" (From Greek hexa: "six" and Latin decima: "a tenth part").