Chmod calculator
Convert Unix permissions from octal (755) to symbolic (rwxr-xr-x) and back, tick boxes and copy the chmod command ready for the terminal.
Like ls -l: rwxr-xr-x or -rwxr-xr-x.
| Who | Read | Write | Execute |
|---|---|---|---|
| Owner | |||
| Group | |||
| Others |
- Command
- chmod 755 file
- Symbolic command
- chmod u=rwx,g=rx,o=rx file
- Like ls -l
- -rwxr-xr-x
How it works
How it works
Unix permissions have three representations and here they stay in sync: octal (755), symbolic (rwxr-xr-x, what ls -l shows) and the checkboxes for owner, group and others. Change any of them and the rest update. Below you get the chmod command in both forms, ready to copy, and a sentence that explains who can do what.
Each octal digit is the sum of read (4), write (2) and execute (1). The first digit is the owner’s, the second the group’s and the third everybody else’s. With four digits, the first one holds the special bits: setuid (4), setgid (2) and sticky (1).
Special bits and warnings
In symbolic form, setuid and setgid show up as s in the execute position (or S without execute), and sticky as t (or T). If other users can write, the tool warns you: any user on the system could modify the file. The quick buttons set the usual values: 644 for files, 755 for scripts and directories, and 600 or 700 for private files.
FAQ
What does chmod 755 mean?
Each digit is the sum of read (4), write (2) and execute (1) for the owner, the group and others. 755 = rwx for the owner and r-x for the group and others: the usual choice for scripts and directories.
Why should I avoid 777?
With 777 any user on the system can modify or delete the file. It is almost never needed: 644 is usually enough for web files and 755 for directories.