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Chmod 600

chmod 600 sets the permissions to rw-------: it lets only the owner read and write. Here is exactly what that allows on files and directories, when to use it, and the commands to apply it.

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ClassreadwriteexecuteValue
owner6
group0
others0
Common:
$ chmod 600 file.sh
$ chmod u=rw,g=,o= file.sh
  • • The owner can read and write.
  • • The group can do nothing.
  • • Everyone else can do nothing.

What chmod 600 means

WhoDigitLettersOn a fileOn a directory
owner 6 rw- Can read and modify Can list files (write has no effect without execute)
group 0 --- No access No access
others 0 --- No access No access

Each digit is the sum of read (4), write (2) and execute (1). In ls -l output it looks like this: 

$ ls -l
-rw-------  1 alice  staff  1834 Oct 21 10:30 example.txt
  • The owner can read and write.
  • The group can do nothing.
  • Everyone else can do nothing.

When to use 600

  • SSH private keys
  • .env files and credentials
  • ~/.netrc, ~/.pgpass, kubeconfig

OpenSSH, PostgreSQL’s ~/.pgpass and many other tools refuse to use a credentials file that others can read, with errors like “UNPROTECTED PRIVATE KEY FILE”. 600 fixes them. Use it for .env files on servers, too.

600 is also the default mode for new files, with umask 077.

Is chmod 600 safe?

Yes. Nobody outside the owner can access it at all (except root).

Commands

# One file
chmod 600 file

# Same thing in symbolic form
chmod u=rw,g=,o= file

# Every file under a tree (leaves directories alone)
find /path/to/dir -type f -exec chmod 600 {} +

# Check the result
stat -c '%a %A %n' file    # Linux
stat -f '%Lp %Sp %N' file  # macOS

Avoid chmod -R 600 on a whole tree: it gives files and directories the same mode. The find form above changes only files.

Compare with similar modes

ModeSymbolicDifference
700 rwx------ Gives the owner full access and everyone else nothing
660 rw-rw---- Lets the owner and group read and write, and others nothing
640 rw-r----- Lets the owner read and write, the group read, and others nothing
500 r-x------ Lets only the owner read and execute
400 r-------- Lets only the owner read
000 --------- Gives nobody any access

Other chmod values

777 · 775 · 770 · 755 · 751 · 750 · 744 · 711 · 700 · 666 · 664 · 660 · 644 · 640 · 555 · 500 · 444 · 400 · 000 · 1777 · 2775 · 4755

Need a different combination? Use the Chmod Calculator.

Sources

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Frequently asked questions

What does chmod 600 mean?

chmod 600 sets the permissions to rw-------. The owner can read and write. The group can do nothing. Everyone else can do nothing.

Is chmod 600 safe?

Yes. Nobody outside the owner can access it at all (except root).