Chmod / Linux Permissions Calculator
Click to set permissions visually. Instant numeric and symbolic output.
Numeric (Octal)
644
Symbolic
rw-r--r--
Command Preview
chmod 644chmod 644 filenamePermission Toggles
Read
Write
Execute
Owner
Group
Other
Owner6 = read + write
Group4 = read
Other4 = read
Enter Numeric Code
octal
Type any 3-digit octal code (e.g. 644) to update the toggles and symbolic notation instantly.
Common Presets
How It Works
| Bit | Permission | Octal value | Symbolic | Meaning |
|---|---|---|---|---|
| r | Read | 4 | r-- | View file / list directory |
| w | Write | 2 | -w- | Modify file / create/delete in dir |
| x | Execute | 1 | --x | Run file / enter directory (cd) |
| Combine | 4+2+1=7 | rwx | Read + write + execute (full access) | |
Frequently Asked Questions
- What does chmod mean?
- chmod (change mode) is a Unix/Linux command that changes file and directory permissions. It controls who can read, write, or execute a file.
- What is chmod 755?
- 755 means the owner has full permissions (7), group and others have read+execute (5). Standard for executables and web directories.
- What is chmod 644?
- 644 means owner can read and write (6), group and others can only read (4). Standard for web files like HTML, CSS, and config files.
- What does execute mean for directories?
- For directories, execute means the ability to enter (cd into) the directory. Without it, you cannot list or access files inside even if you have read permission.
- What is the difference between symbolic and numeric chmod?
- Numeric (755) uses octal digits 0-7. Symbolic (rwxr-xr-x) uses letters. Both represent the same permissions — numeric is faster to type, symbolic is more readable.