Chmod Permissions Calculator
Convert Linux file permissions between octal (755), symbolic (u=rwx) and ls -l, and copy the chmod command.
Such as 644, 0755 or 4755
u=rwx,g=rx,o=r, go-w or -rwxr-xr-x
| Who | Read (4) | Write (2) | Execute (1) | Digit |
|---|---|---|---|---|
| Owner u | 7 | |||
| Group g | 5 | |||
| Others o | 5 |
- Octal
- 755
- Symbolic
- u=rwx,g=rx,o=rx
- ls -l
- -rwxr-xr-x
- Owner can read, change and run
- Group can read and run
- Others can read and run
chmod 755 filenamex on a folder means you can open it (cd into it) and reach its files.
Chmod Permissions Calculator FAQ
What does chmod 755 mean?
The owner can read, write and run the file (7 = 4 + 2 + 1), while the group and everyone else can read and run it (5 = 4 + 1). It is the usual mode for scripts, programs and website folders.
What is the difference between chmod 644 and 755?
644 lets the owner read and write and everyone else only read, which suits ordinary files such as web pages and images. 755 adds execute permission for everyone, which programs, scripts and folders need.
Is chmod 777 safe?
No. 777 lets every user and every program on the server change or replace the file, which attackers can use. Use 755 for folders and 644 for files instead, and give write access only to the owner.
What permissions should an SSH private key have?
Use 600 (or 400), so only you can read it. ssh refuses keys that other users can read and shows an "unprotected private key file" error.
What do setuid, setgid and the sticky bit do?
setuid (4000) runs a program with its owner's rights, setgid (2000) on a folder gives new files the folder's group, and the sticky bit (1000) on a folder such as /tmp lets only a file's owner delete it. They form the first of four digits, as in 4755.
Does this tool change any files?
No. It only calculates modes and builds the command in your browser; you run chmod yourself on your own computer or server.