Chmod Calculator
Calculate Unix file permissions with interactive checkboxes, octal, and symbolic notation
644
rw-r--r--Common Presets
chmod Commands
Octal
chmod 644 filenameSymbolic
chmod u=rw,g=r,o=r filenameChmod Calculator
Calculate Unix file permissions with interactive checkboxes, octal, and symbolic notation
Features
- Interactive checkboxes for owner, group, and others permissions
- Real-time octal and symbolic notation display
- Common permission presets (644, 755, 777, etc.)
- Direct octal input with instant checkbox sync
- Copy-ready chmod commands in both formats
- 100% client-side — no data sent to servers
How to use
- Toggle the read, write, and execute checkboxes for each user group.
- Or type an octal value (e.g., 755) in the input field.
- Or click a common preset button.
- Copy the generated chmod command to use in your terminal.
Tips & Best Practices
- 644 is the standard for files, 755 for directories.
- Never use 777 in production — it grants full access to everyone.
- 600 is recommended for private keys and sensitive config files.
FAQ
What does chmod 755 mean?
755 means the owner can read, write, and execute (7), while group and others can only read and execute (5). This is the standard permission for directories and executable scripts.
What does chmod 644 mean?
644 means the owner can read and write (6), while group and others can only read (4). This is the standard permission for regular files.
What is the difference between octal and symbolic notation?
Octal uses numbers (e.g., 755) while symbolic uses letters (e.g., rwxr-xr-x). Both achieve the same result — octal is more concise, symbolic is more readable.