Binary to Octal Converter
Convert binary to octal by grouping 3 bits at a time. Each group is displayed so you can see exactly how it works. Free, instant, and accurate.
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How to Convert Binary to Octal (3-bit Groups)
Group binary digits into sets of 3 from the right (pad left with zeros if needed). Each 3-bit group equals one octal digit (0–7).
Binary: 11000101 Padded: 011 000 101 Octal: 3 0 5 Result: 305₈
This works because 2³ = 8 — three binary bits represent exactly 8 values (000 to 111), matching the 8 octal digits (0–7).
Frequently Asked Questions
How do you convert binary to octal?
Group bits in 3s from right, pad left with zeros. Convert each group: 000=0, 001=1, 010=2, 011=3, 100=4, 101=5, 110=6, 111=7.
What is 11111111 in octal?
11111111 → 011|111|111 = 3|7|7 = 377₈ (= decimal 255).