Decimal to Octal Converter

Decimal is the base-10 number system used in everyday counting, built from the digits 0–9. It's the format humans read and reason about naturally, which is why programmers convert binary, octal, and hexadecimal values back to decimal whenever they need a human-readable number.

Octal is the base-8 number system, using digits 0–7. Because each octal digit maps exactly to 3 binary bits, it was historically popular for compactly displaying binary data on systems with word sizes divisible by 3. Today its main practical use is Unix/Linux file permissions, expressed as three-digit octal numbers like 755.

To convert decimal to octal, repeatedly divide the number by 8 and record the remainder at each step; reading the remainders from last to first gives the octal value. For example, 10 ÷ 8 = 1 r2, 1 ÷ 8 = 0 r1 — read bottom-up, that's 12. The same process converts 202 to 312.