Octal

Octal Number System

The **octal** numeral system, or **oct** for short, is the base-8 number system, and uses the digits 0 to 7. Numerals can be made from binary numerals by grouping consecutive binary digits into groups of three (starting from the right). For example, the binary representation for decimal 74 is 1001010, which can be grouped into (00)1 001 010 — so the octal representation is 112. In decimal systems each decimal place is a base of 10. For example: In octal numerals each place is a power with base 8. For example: By performing the calculation above in the familiar decimal system we see why 112 in octal is equal to 64+8+2 = 74 in decimal.



Binary to Octal conversion The process is the reverse of the previous algorithm. The binary digits are grouped by threes, starting from the decimal point and proceeding to the left and to the right. Add leading 0s (or trailing zeros to the right of decimal point) to fill out the last group of three if necessary. Then replace each trio with the equivalent octal digit. For instance, convert binary 1010111100 to octal: Thus 10101111002 = 12748 Convert binary 11100.01001 to octal: Thus 11100.010012 = 34.228media type="custom" key="7432593"
 * 001 || 010 || 111 || 100 ||
 * 1 || 2 || 7 || 4 ||
 * 011 || 100 || . || 010 || 010 ||
 * 3 || 4 || . || 2 || 2 ||