What is Chmod Calculator Online?
Unix file permissions control who can read, write, and execute a file. Every file has three permission groups — owner, group, and other — each with read (r=4), write (w=2), and execute (x=1) bits. Chmod (change mode) modifies these permissions, and the octal notation (e.g., 755) is the compact representation used in scripts and documentation.
How to Use Chmod Calculator Online
- Toggle the read/write/execute checkboxes for Owner, Group, and Other.
- The octal code (e.g., 755) and symbolic notation (rwxr-xr-x) update instantly.
- Copy the chmod command to use in your terminal.
Example
Standard executable permission
Input
rwxr-xr-xOutput
755 → chmod 755 file.shFrequently Asked Questions
What does chmod 755 mean?
Owner has full permissions (rwx=7), group has read+execute (r-x=5), and others have read+execute (r-x=5). This is standard for web server files.
What does chmod 644 mean?
Owner has read+write (rw-=6), group has read-only (r--=4), others have read-only (r--=4). This is standard for web content files and SSH public keys.