Octal Converter
Convert octal (base 8) to decimal or decimal to octal. Digits 0–7 only. Unix file permissions (chmod) are often written in octal.
Convert
Enter value and click Convert.
How it works
Octal uses digits 0–7. Each digit is a power of 8. Same idea as hex: parse or format with base 8.
When to use it
Use for file permissions (e.g. chmod 755) or legacy systems.
Frequently asked questions
- Where is octal used? Unix file permissions (e.g. 755) are often written in octal.