Permissions Calculator

chmod 664

Unix file permission mode 664 explained in detail.

Symbolic Notation
-rw-rw-r--(as shown by ls -l)
-rw-rw-r--
typeownergroupother
Permission Matrix
Read(4)Write(2)Execute(1)Octal
Ownerrw-6
Grouprw-6
Otherr--4
What Does chmod 664 Mean?

Owner can read, write. Group can read, write. Others can read.

$ chmod 664 filename
Common Use Cases

Owner and group can read and write; others can read. Common default on systems where the user's primary group is private.

Security Notes

Acceptable when others should be able to read but not write. Be cautious on shared hosting where 'others' includes untrusted users.

Other Common Modes
Interactive Tool

Need to calculate a custom permission? Use the interactive permissions calculator to toggle individual bits and get instant results.

Unix Permissions Calculator