In the Hexadecimal number often shortened “hex”, is a number system which is made up of 16 symbols it means the base of this number system is 16.

The standard number system is called decimal number system; it uses 10 symbols for representation and the 10 symbols are 0,1,2,3,4,5,6,7,8,9. That means in decimal number system the base is 10. Using this number system we can’t represent values greater than 9. In hexadecimal number system letters taken from English alphabet, specifically A, B, C, D, E and F. Hexadecimal “A” represent the decimal number 10, and hexadecimal “ F” is equal to the decimal number 15.

Humans mostly use decimal number probably because of having ten fingers on their hand. But computer however have only on and off, called a binary digit. A binary number is just combination of 0s and 1s.

Hexadecimal number is mostly similar to the octal number system. This number system uses four-bit binary coding. It means each digit in hexadecimal number is the same as four digit binary number.

In the decimal number system, the first digit is the one’s place, the next digit to the left of first digit is the ten’s place, the next is the hundred’s place, etc. But in hexadecimal number system, each digit can be 16 values, not 10. So we can say the digits have the one’s place, the sixteen’s place, and the next one is the 256’s place. So 1hexadecimal = 1 decimal, 10hexadecimal = 16 decimal, and 100hexadecimal = 256 in decimal.

 Hex Binary Octal Decimal 0 0 0 0 1 1 1 1 2 10 2 2 3 11 3 3 4 100 4 4 5 101 5 5 6 110 6 6 7 111 7 7 8 1000 10 8 9 1001 11 9 A 1010 12 10 B 1011 13 11 C 1100 14 12 D 1101 15 13 E 1110 16 14 F 1111 17 15 10 1 0000 20 16 11 1 0001 21 17 24 10 0100 44 36 5E 101 1110 136 94 100 1 0000 0000 400 256 3E8 11 1110 1000 1750 1000 1000 1 0000 0000 0000 10000 4096 FACE 1111 1010 1100 1110 175316 64206

There are two common ways to convert a number from hexadecimal numbers to decimal, there are two common ways.

The first approach is more ordinarily done when it is manually conversion:

1. At first have to use the decimal value for each hexadecimal digit. It is the same for the number 0 to 9, but the values of A, B, C, D, E, F are 10, 11, 12, 13, 14, 15 respectively.
2. Keep a sum of the products changed at each step below.
3. Start with the least significant hexadecimal digit, digit on the right end. In a sum this will be the first item. This item will be the first item in a sum.
4. Take the second-least significant digit, next to the digit on the right end. Multiply the decimal number digit by 16. Add the number to the sum.
5. Do the same for the third-least vital digit, but multiply it by 162 (that is, 16 squared, or 256). Add it to the sum.
6. Continue for each digit, adding each place by another power of 16. (4096, 65536, etc.)
 Location 5 4 3 2 1 Value 65536 (164) 4096 (163) 256 (162) 16(161) 1 (160)

In the time converting a number in software the next method is more commonly done. It does not require to know how many numbers has before when it starts, and it never multiplies by more than 16, but it looks longer on paper.

1. At first have to use the decimal value for each hexadecimal digit. It is the same for the number 0 to 9, but the values of A, B, C, D, E,F are 10, 11, 12, 13, 14, 15 respectively
2. Keep a sum of the numbers changed at each step below.
3. Start among the various important digit (the digit on the far left). This is the first item in the sum.
4. If there is another digit, multiply the sum by 16 and then add the decimal value of the next digit.
5. Repeat the high step until there are no more digits.

Example: 5F hexadecimal to decimal, method 1

(5F)16 = (5 x 16) + (15 x 1)

= 80 + 15

= (95)10

Example: 5F hexadecimal to decimal, method 2

Sum= (5 x 16) + 15

= 80 + 15

= (95)10

There are some steps for converting one binary number system to hexadecimal number system:-

1. At first we have to underline each pair of the digits from right side to left. If any bit is left in the left side of the digit this will be the last set of pair.
2. After that convert the each 4 digit set in to equivalent hexadecimal number.
3. Then rewrite the digit which we get after the conversion.

Example: Convert (1010010100)2 to equivalent hexadecimal number.

0010 1000 0100

2 8 4

Ans. (284)16