How do you convert decimal to octal?

Divide the decimal number by 8 repeatedly, keeping track of the remainders (which will be 0-7). Read the remainders from bottom to top to get the octal representation. For example, 64: 64÷8=8 remainder 0, 8÷8=1 remainder 0, 1÷8=0 remainder 1. Result: 100.

What is decimal 64 in octal?

Decimal 64 in octal is 100. You can verify: (1×8²) + (0×8¹) + (0×8⁰) = 64 + 0 + 0 = 64.

Why use octal instead of decimal or hexadecimal?

Octal is mainly used for Unix file permissions, where it's convenient because each octal digit represents exactly three permission bits (read, write, execute for owner/group/others). It's also used in some legacy systems and educational contexts.

How are Unix file permissions represented in octal?

Unix permissions use three octal digits: first digit for owner, second for group, third for others. Each digit is sum of: 4 (read), 2 (write), 1 (execute). For example, 755 means owner has 7 (read+write+execute), group and others have 5 (read+execute).

What's the difference between octal and hexadecimal?

Octal uses base 8 (digits 0-7), while hexadecimal uses base 16 (digits 0-9, A-F). Octal groups binary into sets of 3 bits, hexadecimal into sets of 4 bits. Hexadecimal is more common in modern computing, while octal is mainly used for Unix permissions.

Can I convert negative decimal numbers to octal?

Yes, but you need to specify the representation format. For signed numbers, you might use sign-magnitude or complement representations. Our converter handles unsigned (positive) numbers by default.

🔢 Decimal to Octal Converter

Convert decimal numbers to octal instantly. Free online decimal to octal converter with detailed steps for quick and accurate conversions.

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Conversion: Decimal → Octal

Octal (base 8) is a number system that uses digits 0-7, where each digit represents three binary bits. While less common than hexadecimal in modern computing, octal is still important for Unix file permissions, some legacy systems, and educational purposes. This converter helps you transform decimal numbers into octal format quickly and accurately.