HOW TO CONVERT ANY HEX NUMBER TO DECIMAL and BINARY
Go directly to EXAMPLE CONVERSION  HEX TO BINARY
EXAMPLE CONVERSION  HEX TO DECIMAL
Hex  Decimal Equivalent 
9AC3  39,619 
Hex=Decimal  Comment  Hexadecimal number to be converted 
Decimal Equivalent 

0=0 1=1 2=2 4=4 5=5 6=6 7=7 8=8 9=9 A=10 B=11 C=12 D=13 E=14 F=15 
Columns are numbered from right to left, starting at column zero, not column one  column 3 
column 2 
column 1 
column 0 

Write the hex number with one digit per column  9  A  C  3  
Convert the hex digit to decimal  9  10  12  3  
Multiply each digit by 16 to the power of n, where n is the column number  9 x (16^3)  10 x (16^2)  12 x (16^1)  3 x (16^0)  
Put the answer in this row, and add all the answers together  36,864  + 2,560  + 192  + 3  = 39,619 
DEFINITIONS:
16^3 = 16 to the power of 3 = (16 x 16 x 16) = 4,096
16^0 = 16 to the power of 0 = 1 (anything to the power of zero equals one.)
EXPLANATION:
Each hex digit is multiplied by 16^n, where n is its column number, numbering from right to left, starting at column zero (not column 1).
Then all the answers are added together. This gives you the decimal equivalent of the hex number you started with.
A GENERAL FORMULA CAN BE DERIVED FOR THOSE FAMILIAR WITH MATHEMATICAL NOTATION
Decimal Equiavalent = Σ (Hn x 16^n) from n = 0 to n
where Σ means "sum", n is the column number, and Hn is the hex digit in the nth column
EXAMPLE CONVERSION  HEX TO BINARY
Hex  Binary Equivalent 
9AC3  1001 1010 1100 0011 
Hex=Binary  Comment  Hexadecimal number to be converted 
Binary Equivalent  
0=0000 1=0001 2=0010 3=0011 4=0100 5=0101 6=0110 7=0111 8=1000 9=1001 A=1010 B=1011 C=1100 D=1101 E=1110 F=1111 
Hex is directly related to binary and the order of conversion does not matter. You can start at column 3 or column zero.  column 3 
column 2 
column 1 
column 0 

Write the hex number with one digit per column  9  A  C  3  
Convert each hex number directly into binary  1001  1010  1100  0011  
The usual use of binary is in computers where the binary digits are called bits and are grouped by 8's to make one byte (one byte = 8 bits)  1001 1010  1100 0011  1001 1010 1100 0011 