Decimal to Octal Conversion

Convert between Decimal and Octal quickly and accurately.

dec
oct

How to Convert Decimal to Octal

Conversion Formula

1 dec = 1.25 oct
1 oct = 0.8 dec

Example

Convert 15 dec to oct:

15 dec = 15 × 1.25 oct = 18.75 oct

Unit Information

Learn about the numbers units you're converting between

Decimal

dec

Definition

Decimal is a base-10 numeral system using digits 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. It is the most widely used numeral system in the world, forming the foundation of modern mathematics.

History/Origin

Decimal systems have been used for thousands of years, likely originating from counting on ten fingers. The Hindu-Arabic numeral system standardized decimal notation.

Current Use

Decimal is used in all aspects of daily life, mathematics, science, engineering, finance, and virtually every field that involves numbers.

Multiplier

10

Offset

0

Octal

oct

Definition

Octal is a base-8 numeral system using digits 0, 1, 2, 3, 4, 5, 6, and 7. It was historically important in early computer systems and is still used in some programming contexts.

History/Origin

Octal was widely used in early computer systems, particularly in the 1960s and 1970s. It was popular because it maps easily to binary (3 bits per octal digit).

Current Use

Octal is used in some programming languages, file permissions (Unix/Linux), and certain computer science applications.

Multiplier

8

Offset

0

Decimal to Octal Conversion Table

Decimal [dec] Octal [oct]
1 dec 1.25 oct
10 dec 12.5 oct
25 dec 31.25 oct
50 dec 62.5 oct
100 dec 125 oct
0 dec 0E+0 oct
-10 dec -12.5 oct
-40 dec -50 oct