CHMOD Calculator

Select permissions for Owner, Group and Others to get the numeric and symbolic CHMOD notation instantly.

Select file permissions

Owner
Group
Others

Linux permissions

Numeric notation 000
Symbolic notation ---------

What this tool does

The CHMOD calculator presents the nine classic Unix file permissions as clear switches.

Your selection instantly produces the three-digit octal value and symbolic notation.

How to use the tool

  1. Enable Read, Write and Execute separately for Owner, Group and Others.
  2. Read the matching CHMOD value and permission string directly below the switches.

Useful applications

  • Assemble common permissions such as 644 or 755 before using them on a server.
  • Compare permission combinations by turning individual switches on and off.

Notes and limitations

  • Read counts as 4, Write as 2 and Execute as 1; their sum becomes the digit for each user class.
  • The calculator covers only the nine basic permissions and excludes special bits such as Setuid, Setgid and the sticky bit.

Frequently asked questions

What does the value 755 mean?

Owner can read, write and execute; Group and Others can read and execute.

Does the calculator change actual file permissions?

No, the tool only calculates and displays the notations in your browser.

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