Chmod Calculator
Calculate Unix file permissions with an interactive chmod calculator. Convert between octal (755) and symbolic (-rwxr-xr-x) formats.
Our Chmod Calculator makes it easy to generate the correct permission codes for your files and directories.
- Select Permissions for Each Group: Use the interactive grid to check or uncheck options for Owner, Group, and Others. You can set Read (r), Write (w), and Execute (x) permissions for each.
- View Instant Results: As you modify the checkboxes, the Octal (e.g., 755) and Symbolic (e.g., -rwxr-xr-x) values update automatically.
- Input Octal Values: If you already have a number like '777', type it into the Octal input box. The tool will instantly update the checkboxes to match.
- Copy to Clipboard: Click the copy icon next to any value to copy the permission string to your clipboard for immediate use in your terminal.
- Visual Permission Grid: Intuitive checkbox interface eliminates the need for mental math when calculating permissions.
- Bi-directional Conversion: Change permissions via the grid or by typing the Octal code directly; both sync instantly.
- Octal & Symbolic Support: Get both the numeric sets (e.g., 644) and the symbolic string (e.g., -rw-r--r--) simultaneously.
- Client-Side Privacy: All calculations happen right in your browser. No data is sent to any server, ensuring your configurations remain private.
- Instant & Responsive: Designed for speed and compatibility with all modern devices and screen sizes.
Managing file permissions in Unix-like systems can be confusing, especially when trying to remember the exact numeric values for specific combinations. Our Chmod Calculator simplifies this process by providing a clear, visual interface.
It allows you to experiment with different permission settings safely before applying them to your production files. With its fast, client-side execution, you get instant feedback without any latency. Whether you are a seasoned system administrator or a beginner learning Linux commands, this tool ensures you get the exact permissions you need every time, error-free and completely free of charge.
What is Chmod?
Chmod (short for "change mode") is a command-line utility in Unix and Linux systems used to change the access permissions of file system objects like files and directories.
How are permissions calculated?
Permissions are calculated using octal values: Read = 4, Write = 2, and Execute = 1. These are summed up for each user group. For example, Read + Write = 4 + 2 = 6.
What does 755 mean?
755 is a common permission setting. The first digit (7) gives the Owner full permissions (Read+Write+Execute). The second (5) and third (5) digits give the Group and Others read and execute permissions only.
What is the difference between Octal and Symbolic?
Octal notation uses numbers (0-7) to represent permissions, which is concise and often used in scripts. Symbolic notation uses characters (r, w, x, -) to clearly display what actions are allowed.