Octal number system

  • The number system with base/radix  8 is known as octal number system.
  • 8 symbols/digit are used in it (0,1, 2, 3, 4, 5, 6 & 7) to represent a number.
  • Octal number system is positional number system, i.e. every position in a number has assigned some weight.
  • Octal number system provides a convenient way of converting large binary numbers into more compact and smaller groups.
  • In general, Octal number can be expressed as:

  • For example , (345.67)8 is an octal number while 785.67 is not.
  • Octal numbers are shown below,
octal numbers binary numbers decimal
equivalent
0 0 0 0   0
1 0 0 1  1
2 0 1 0  2
3 0 1 1  3
4 1 0 0 4
5 1 0 1  5
6 1 1 0  6
7 1 1 1  7
1 0 001 000 8
1 1 001 001 9
1 2 001 010 10
1 3 001 011 11

conversion from decimal to octal number       
conversion from octal to decimal number                                                                                                                                                                   back to DIGITAL ELCTRONICS