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Chmod Calculator

Calculate Unix file permissions with an interactive checkbox grid. Convert between numeric and symbolic notation.

Frequently Asked Questions

What does chmod 755 mean?

Chmod 755 sets the file owner to have read, write, and execute permissions (7), while the group and others have read and execute permissions (5). This is the most common permission for executable scripts and public directories.

How do I convert chmod numeric to symbolic?

Enter the numeric value (e.g., 644) in the calculator and it will show the symbolic equivalent (e.g., rw-r--r--). Each digit represents permissions for owner, group, and others: 4=read, 2=write, 1=execute.

What is the difference between chmod 644 and 755?

Chmod 644 (rw-r--r--) is typically used for regular files — the owner can read and write, everyone else can only read. Chmod 755 (rwxr-xr-x) adds execute permission, which is needed for scripts and directories.