Decimal to Octal Conversion

This tool converts numbers between the decimal system (base-10) and the octal system (base-8).

How to Use This Converter

• Enter a decimal number (e.g., 64) to get the equivalent in octal
• Or input an octal number (e.g., 100) to get its decimal value

Supports two-way conversion between decimal and octal values.

Understanding the Conversion

Octal (base-8) uses digits from 0 to 7. It's particularly useful in computing because each octal digit directly represents 3 bits of binary data.

Example:

• Decimal 64 = Octal 100
• Decimal 83 = Octal 123
• Decimal 255 = Octal 377

Example

Convert decimal 200 to octal:

1. 200 ÷ 8 = 25 remainder 0
2. 25 ÷ 8 = 3 remainder 1
3. 3 ÷ 8 = 0 remainder 3
4. Read remainders in reverse: 310

Result: 200₁₀ = 310₈

Octal Reference Table (0-63)

Why Use Octal?

Octal was historically used in Unix file permissions and in older mainframe computing. While less common than hexadecimal, it's still useful for compactly representing binary data in groups of 3 bits.

Example: Unix file permissions like chmod 755 are in octal!