Chmod Calculator

A free utility to calculate the numeric (octal) or symbolic value for a set of file or folder permissions in Linux servers.

How to use

Check the desired boxes or directly enter a valid numeric value (e.g. 777) or symbolic notation (e.g. rwxrwxrwx) to see its value in the other formats.

Result

Octal

755

Symbolic

rwxr-xr-x

Numeric

493

chmod command

chmod 755 filename

Human-readable

Owner: read + write + execute
Group: read + execute
Public: read + execute

Octal input

3 or 4 digits (0-7)

Symbolic input

9 chars: r/w/x/-

chmod-style input

Applied on top of current perms

Quick reference

755

rwxr-xr-x

Common: files

644

rw-r--r--

Common: files

700

rwx------

Private dir

777

rwxrwxrwx

Full access

600

rw-------

Private file

775

rwxrwxr-x

Shared dir

664

rw-rw-r--

Shared file

400

r--------

Read-only

File permissions in Linux are managed in three distinct user classes: owner, group, and others. Each class can have read (r), write (w), and execute (x) permissions. A permission can be represented in symbolic (rwxr-xr-x) or numeric octal (755) format.

Read (r = 4) — view file contents / list directory
Write (w = 2) — modify file / add or remove entries
Execute (x = 1) — run file / enter directory

The three digits in the octal form correspond to owner, group, and others respectively. Each digit is the sum of its enabled bits (4 + 2 + 1 = 7 for full access).

File Permissions

File permissions in a Linux file system are managed in three distinct user classes: user/owner, group, and others/public. Each class can have read, write, and execute permissions. File permission can be represented in a symbolic or numeric (octal) format.