Binary to Octal Converter

Binary to Octal Converter

Quick Examples

Advanced: Convert Any Base (2-36)

Understanding Binary and Octal

Binary is the base-2 number system used natively by computers: every value is stored as a sequence of bits, each either 0 or 1. Digital logic gates, boolean operations, and low-level memory all operate directly in binary — it's the only number system a CPU actually understands.

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.

How to Convert Binary to Octal (Step by Step)

To convert binary to octal, group the bits into sets of 3 starting from the right (padding the leftmost group with zeros if needed), then convert each group to a single octal digit. For example, 11001010 splits into 011 001 010, which is 3, 1, 2 — giving 312.

Frequently Asked Questions

Find answers to common questions

To convert binary to octal, group the bits into sets of 3 starting from the right (padding the leftmost group with zeros if needed), then convert each group to a single octal digit. For example, 11001010 splits into 011 001 010, which is 3, 1, 2 — giving 312.
Because each octal digit maps to exactly 3 bits with no remainder, converting binary to octal is a simple grouping operation you can do without any arithmetic — useful for quickly reading long bit strings, such as Unix file permission bits.
No — this converter uses arbitrary-precision (BigInt) math internally, so it produces exact results even for very long binary strings or huge decimal, octal, and hexadecimal values, unlike calculators limited to 32-bit or 64-bit integers.

Free online binary to octal converter. Convert binary numbers to octal instantly, with support for arbitrarily large values.

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