Chmod Calculator

Calculate Linux file permissions with an interactive chmod calculator. Convert between octal, symbolic, and checkbox representations instantly.

File Permissions
Read (4) Write (2) Execute (1)
Owner
Group
Others
Special Permissions
chmod 000 filename
Common Presets

Frequently Asked Questions

How do Linux file permissions work?
Linux file permissions control who can read, write, or execute a file. Permissions are set for three groups: owner, group, and others. Each group can have read (r), write (w), and execute (x) permissions.
What does chmod 755 mean?
chmod 755 means the owner has full permissions (read, write, execute), while the group and others can only read and execute. In symbolic notation this is rwxr-xr-x. It is the most common permission for executable files and directories.
What are setuid, setgid, and sticky bit?
Setuid (4) runs a file as the file owner. Setgid (2) runs it as the group owner or inherits group in directories. Sticky bit (1) prevents users from deleting files they do not own in shared directories like /tmp.
Is my data safe when using this chmod calculator?
Yes. All calculations happen entirely in your browser. No data is ever sent to a server.