Super User is a question and answer site for computer enthusiasts and power users. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

What does chmod 654 stand for ?

share|improve this question

migrated from Aug 30 '10 at 10:39

This question came from our site for professional and enthusiast programmers.

(reference) or just man chmod in your shell – Gordon Aug 30 '10 at 10:36


0 --- no permission
1 --x execute 
2 -w- write 
3 -wx write and execute
4 r-- read
5 r-x read and execute
6 rw- read and write
7 rwx read, write and execute

First number represents the owner, second the group and the third everyone. So 654 would mean read and write for owner, read and execute for group and only read for everyone else.

share|improve this answer
It's simple math really, and pretty handy to know in some cases. Execute is 1, write is 2, read is 4. The resulting permissions are additions of these three. Maybe it was clear from that table, but I myself didn't really think of it at first. Voting up your answer. – JaHei Aug 30 '10 at 13:37

It stands for -rw-r-xr--. See also the chmod man pages.

share|improve this answer

As others have said, it's rw-r-xr--, which gets stored as a series of bits, 110101100. Split that into user, group, owner blocks and you get 110 101 100. Representing those binary numbers as octal gets you 6 5 4. Tada!

share|improve this answer
+1: Very nicely explained! – Dave Sherohman Jun 28 '11 at 9:24

Change permissions to rw-r-xr--.

Here's a chmod calculator:

share|improve this answer

You must log in to answer this question.