Binary to Octal Converter
Convert binary to octal: group bits in threes from the right, map each group to 0–7. Free programmer base-2 to base-8 tool.
How to Convert Binary to Octal
Pad binary to multiple of 3 bits, group in threes, convert each group to one octal digit.
Group binary in 3-bit chunks from the right; each group is one octal digit (0–7).
101011₂ → 101 | 011 → 53₈.
Fast because 8 = 2³—no multiplication table needed.
Compact binary display. The table and FAQ on this page walk through the factor if you need it.
Conversion Examples
Example: 101011 to octal
- 101 | 011 → 5 | 3
53 octal
Pad left if needed.
Example: 111111 to octal
- 111 | 111 → 7 | 7
77 octal
Six bits = two octal digits.
Common Use Cases
- Compact binary display.
- CS homework and exams.
- Understanding bit grouping.
- Legacy octal I/O formats.
Frequently Asked Questions
How do you convert binary to octal?
Group bits in threes from the right; each 3-bit group is one octal digit.
Why groups of three?
8 = 2³, so one octal digit equals exactly 3 binary bits.
1010 binary in octal?
Pad to 001 010 → 12 octal.