Chmod Calculator

The Chmod Calculator is a visual tool to help you understand and generate Linux file permissions. In Linux/Unix systems, file permissions determine who can read, write, or execute a file.

Understanding Roles

• Owner: The user who owns the file. Usually the creator.
• Group: A defined group of users who share permissions.
• Public (Others): Everyone else on the system.

Understanding Permissions

• Read (4): Permission to view the file content.
• Write (2): Permission to modify or delete the file.
• Execute (1): Permission to run the file as a program or script.

Common Values

• 755 (rwxr-xr-x): Standard for directories and executable scripts. Owner has full access; others can only read and execute.
• 644 (rw-r--r--): Standard for regular files (like HTML, images). Owner can read/write; others can only read.
• 777 (rwxrwxrwx): Full access for everyone. Use with extreme caution as it is a security risk.
• 400 (r--------): Read-only for the owner, no access for anyone else. Used for sensitive keys.