🔒Chmod Calculator

Calculate Unix file permissions in numeric and symbolic notation.

Numeric Value

Command

chmod 755 filename

Common Presets

About Chmod Calculator

Calculate Unix/Linux file permissions by toggling read, write, and execute checkboxes for owner, group, and others. See both the numeric (octal) notation like 755 and the symbolic notation like rwxr-xr-x update in real time. Essential for setting correct file permissions on servers and in deployment scripts.

How to Use Chmod Calculator

1
Toggle permissions
Check or uncheck the read, write, and execute boxes for owner, group, and others.
2
View the result
See the numeric (octal) and symbolic permission values update in real time.
3
Copy and apply
Copy the chmod command to apply the permissions on your server.

Common Use Cases

Setting correct file permissions on Linux web servers
Understanding permission errors in deployment scripts
Configuring directory permissions for web applications
Learning Unix file permission concepts

Frequently Asked Questions

What does chmod 755 mean?

chmod 755 sets the owner to read, write, and execute (7), the group to read and execute (5), and others to read and execute (5). It is the standard permission for web-accessible directories and executable scripts.

What is the difference between numeric and symbolic notation?

Numeric notation uses octal digits (e.g. 644), where each digit sums read (4), write (2), and execute (1). Symbolic notation uses letters (e.g. rw-r--r--) to show the same permissions in a human-readable format.

What permission should I use for web files?

Common web permissions are 644 (rw-r--r--) for files and 755 (rwxr-xr-x) for directories. Never use 777 in production as it grants full access to everyone.