Umask Calculator
Enter an octal or symbolic umask to see the permissions new files and directories receive by default.
A QUICK WALKTHROUGH
How to use this tool
- Enter an octal umask such as 022, or a symbolic mask such as u=rw,g=r,o=.
- Review the resulting default permissions for a file and a directory.
- Use the result as a reference; this calculator never changes your system umask.
Files and directories start differently
New regular files use a base mode of 0666, while new directories use 0777. The umask removes permission bits from those bases.
Octal and symbolic input
Use a three or four digit octal mask from 000 to 0777, or nine rwx characters such as rwxr-xr-x. Comma-separated u=, g=, and o= clauses are also accepted.
Calculation only
This page only explains and calculates permission modes in your browser. It does not read files, change permissions, or modify the system umask.
GOOD TO KNOW
Common questions
What does umask 022 produce?
New files default to 0644 and new directories default to 0755, subject to the program creating them.
Why are files based on 0666?
Programs normally request 0666 for regular files; execute bits are not included in that starting mode.
Does this change my system umask?
No. It only calculates the result locally and never runs umask or changes a process setting.