Chmod Calculator

Calculate Unix file permissions with an interactive chmod calculator. Click checkboxes or type an octal number.

Permissions Grid

Owner
Group
Others
Read 4
Write 2
Execute 1
Value 7 5 5

Command Preview

$ chmod 755 file.txt

Octal Notation

755

Symbolic Notation

- r w x r w x r w x

Common Presets

Understanding Unix Permissions

Read (4)

Allows viewing file contents or listing directory contents. For files, you can open and read the file. For directories, you can list the files inside.

Write (2)

Allows modifying file contents or adding/removing files in a directory. For files, you can edit or truncate. For directories, you can create or delete files.

Execute (1)

Allows running a file as a program or entering a directory with cd. Scripts need execute permission to run directly.