Chmod Calculator

Calculate Unix file permissions in numeric and symbolic notation. Visual interface with checkboxes, presets, and reverse lookup.

owner

group

others

755
rwxr-xr-x
chmod 755 filename

How to Use

  1. 1

    Set permissions

    Use the checkboxes to set read, write, and execute permissions for Owner, Group, and Others.

  2. 2

    View outputs

    See the numeric notation (e.g., 755), symbolic notation (e.g., rwxr-xr-x), and chmod command automatically generated.

  3. 3

    Use presets or reverse lookup

    Click a preset button to apply common permissions, or enter a numeric value to update the checkboxes.

  4. 4

    Copy command

    Copy the chmod command to use in your terminal.

Chmod (change mode) is a Unix command that sets file permissions. Permissions control who can read, write, or execute a file. The numeric notation uses octal values (0-7) for each permission group.

  • Setting web server file permissions
  • Securing private keys (400 or 600)
  • Making scripts executable
  • Troubleshooting permission denied errors
  • Configuring deployment permissions