Octal to Binary Converter
Convert octal (base-8) numbers to binary (base-2) format instantly. Free online octal to binary converter with batch conversion support.
Input
Output
What is Octal to Binary Conversion?
Octal to binary conversion transforms numbers from <a href="https://en.wikipedia.org/wiki/Octal" target="_blank" rel="noopener">base-8 (octal)</a> to base-2 (binary) representation. Octal uses digits 0-7, while binary uses only 0 and 1. Each octal digit maps to exactly three binary digits (bits), making the conversion straightforward.
To convert octal to binary, replace each octal digit with its 3-bit binary equivalent. This grouping property is why octal was historically popular on systems like the <a href="https://en.wikipedia.org/wiki/PDP-8" target="_blank" rel="noopener">DEC PDP-8</a>, which used 12-bit words. For example, octal 377 = 011 111 111 = 11111111 in binary (leading zeros removed).
How to Use This Converter
Enter Octal Values
Type or paste your octal numbers in the input panel. Enter one number per line for batch conversion. The 0o prefix is optional.
Automatic Conversion
The converter automatically transforms each octal number to its binary equivalent in real time as you type.
Copy or Download Results
Use the Copy button to copy the binary results to your clipboard, or Download them as a text file.
Conversion Examples
Here are some common octal to binary conversions:
Octal Input
Binary Output
Frequently Asked Questions
How does octal to binary conversion work?
Each octal digit directly maps to 3 binary bits. Simply replace each octal digit with its 3-bit binary equivalent: 0=000, 1=001, 2=010, 3=011, 4=100, 5=101, 6=110, 7=111.
Why convert octal to binary?
Converting octal to binary is useful for understanding Unix file permissions (chmod), analyzing low-level data, and working with legacy systems that use octal notation.
Is octal to binary conversion lossless?
Yes, octal to binary conversion is completely lossless. Each octal digit maps to exactly 3 binary digits, so no information is lost. This is described in detail in the Tutorialspoint number systems guide.
Can I convert multiple octal numbers at once?
Yes! Enter one octal number per line and the converter will process all of them simultaneously.
Related Tools
Learn more about number systems at MDN Web Docs. For further reading on octal notation in programming, see the Python integer literals documentation.