What is the difference between numeric and symbolic chmod?

Numeric (e.g., chmod 755) sets absolute permissions using octal digits. Symbolic (e.g., chmod u+x) adds or removes specific permissions relative to the current state. Both achieve the same result.

What does the sticky bit do?

The sticky bit (chmod +t or 1xxx) on a directory prevents users from deleting files they do not own. The /tmp directory typically has the sticky bit set (1777).

Chmod Permissions Calculator in Your Browser

Use an interactive visual interface to set file permissions. Toggle checkboxes for read, write and execute on owner, group and others, and see the corresponding chmod command, octal value and symbolic notation update in real time.

Open Chmod Calculator

How to Use the Calculator

Toggle read (r), write (w) and execute (x) for each category
View the octal value (e.g., 755) update in real time
See the symbolic notation (e.g., rwxr-xr-x) alongside
Copy the full chmod command to your clipboard

Common Use Cases

Quickly building chmod commands for deployment scripts
Understanding existing permission values on server files
Teaching file permissions to new team members
Debugging permission denied errors

Frequently Asked Questions

What is the difference between numeric and symbolic chmod?: Numeric (e.g., chmod 755) sets absolute permissions using octal digits. Symbolic (e.g., chmod u+x) adds or removes specific permissions relative to the current state. Both achieve the same result.
What does the sticky bit do?: The sticky bit (chmod +t or 1xxx) on a directory prevents users from deleting files they do not own. The /tmp directory typically has the sticky bit set (1777).