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DataToolings

Chmod Calculator

Calculate Unix/Linux file permissions

Ownerrwx (7)
Groupr-x (5)
Othersr-x (5)

Octal

755

Symbolic

rwxr-xr-x

chmod command

chmod 755 filename

What is Chmod?

Chmod (change mode) is a Unix/Linux command that sets file and directory permissions. Permissions control who can read, write, or execute a file — for the owner, group, and others. This calculator lets you toggle permission bits visually and instantly shows the octal notation (e.g. 755) and symbolic notation (e.g. rwxr-xr-x) used with the chmod command.

How to Use the Chmod Calculator

  1. Toggle the read, write, and execute checkboxes for Owner, Group, and Others
  2. The octal value and symbolic notation update instantly
  3. Copy the octal value or the full chmod command
  4. Run the command in your terminal: chmod 755 filename

Chmod Calculator Features

  • Visual permission toggle for owner, group, and others
  • Instant octal notation (e.g. 755, 644)
  • Symbolic notation (e.g. rwxr-xr-x)
  • Ready-to-run chmod command output
  • Common permission presets for quick reference

Chmod Calculator FAQ

What does 755 mean?

755 means the owner has read+write+execute (7), and group and others have read+execute (5). Common for directories and executable scripts.

What does 644 mean?

644 means the owner has read+write (6), and group and others have read-only (4). Common for regular files.

What is the difference between 755 and 777?

777 gives everyone full read+write+execute permissions, which is a security risk. 755 restricts write access to the owner only.