Chmod Calculator Linux

Calculate and convert Linux file permissions instantly. Interactive chmod permissions calculator with numeric and symbolic notation support.

Interactive Chmod Calculator

Select permissions or enter numeric/symbolic notation

Owner
Group
Others
Special Permissions
chmod 644 filename

Owner can read, write. Group can read. Others can read.

Common Permission Presets

Click to quickly apply common chmod configurations

Understanding Chmod Permissions

Numeric Notation

Each digit represents permissions for owner, group, and others. Values are calculated by adding: Read (4) + Write (2) + Execute (1).

Symbolic Notation

Shows permissions as a 9-character string: rwxrwxrwx. Each group of three represents owner, group, and others permissions.

Chmod Calculator Features

Interactive Calculator

Visual checkbox interface for easy permission selection

Instant Conversion

Convert between chmod number codes and symbolic notation in real-time

Special Permissions

Support for SETUID, SETGID, and Sticky bit

History Tracking

Keep track of your recent calculations

Favorites

Save frequently used permission configurations

Quick Copy

One-click copy for commands and notations

How to Use the Chmod Command

Chmod Number Calculator - Numeric Notation

Numeric (octal) notation uses three or four digits to represent permissions:

  • 4Read permission
  • 2Write permission
  • 1Execute permission

Add these values together for each user category (owner, group, others).

chmod 755 filename

This gives owner full permissions (7=4+2+1), and group/others read+execute (5=4+1)

Chmod Symbolic Calculator - Symbolic Notation

Symbolic notation uses letters to represent permissions:

  • rRead permission
  • wWrite permission
  • xExecute permission
  • -No permission

Format: owner-group-others (9 characters total)

rwxr-xr-x

Owner: read+write+execute, Group: read+execute, Others: read+execute

Chmod Examples - Common Permission Values

About Chmod and File Permissions

The chmod command (change mode) is a fundamental tool in Linux and Unix-based operating systems used to control file and directory permissions. Our chmod value calculator helps you understand and properly configure file permissions, which is crucial for system security and proper access control.

File permissions in Linux are divided into three categories: Owner (the user who owns the file), Group (users who are members of the file's group), and Others (all other users). Each category can have three types of permissions: read (r), write (w), and execute (x).

This chmod permissions calculator makes it easy to visualize and convert between different permission notations. Whether you're a system administrator, developer, or Linux enthusiast, our chmod number calculator helps you quickly determine the correct permissions for your files and directories, including chmod recursive operations.

Special permissions like SETUID, SETGID, and the Sticky bit provide additional control over file execution and directory access. These advanced features are fully supported in our calculator.