Chmod Calculator
Calculate Linux/Unix file permissions visually. Convert between octal and symbolic notation.
Owner (u)
Octal7
Group (g)
Octal5
Others (o)
Octal5
Common Permission Presets
Frequently Asked Questions
What is chmod?
chmod (change mode) is a Unix/Linux command that changes file and directory permissions. It controls who can read, write, and execute files. Permissions are set for three groups: Owner, Group, and Others.
What does 755 mean?
755 means the owner has full permissions (read + write + execute = 7), while group and others can read and execute but not write (read + execute = 5). This is the standard permission for directories and executable scripts.
What is the difference between octal and symbolic notation?
Octal notation uses 3 digits (e.g., 755) where each digit represents permissions for owner, group, and others. Symbolic notation uses letters (e.g., rwxr-xr-x) where r=read, w=write, x=execute, and -=no permission.