chmod 666 meaning

666 rw-rw-rw-

The owner, the group and everyone else can read and write.

When to use 666

Files everyone may change, such as /dev/null. On a website, use 664 or 644 instead.

Everyone else can change these files. On shared hosting this lets other accounts or any compromised script modify them.

What each digit allows

Read = 4, write = 2, execute = 1. Each digit is the sum for one group of users.

Who	Digit	Symbolic	Read	Write	Execute
Owner (u)	6	rw-	Yes	Yes	No
Group (g)	6	rw-	Yes	Yes	No
Others (o)	6	rw-	Yes	Yes	No

On a folder, read lists its contents, write adds or deletes files in it, and execute lets you open it (cd into it).

Commands

One file or folder, a folder with everything inside it, or only the files inside a folder:

chmod 666 file.php
chmod -R 666 folder/
find folder/ -type f -exec chmod 666 {} +

In cPanel: File Manager → right-click → Change Permissions, and tick the boxes until the number shows 666.

Try other permissions

Tick or untick the boxes to see the number, the symbolic form and the command.

	Read	Write	Execute
Owner
Group
Everyone else

Special bits (setuid, setgid, sticky)

setuid setgid sticky

Common values

Octal

Symbolic

Command

-R

Compare

Frequently asked questions

What does chmod 666 mean?

Each digit is the sum of read (4), write (2) and execute (1), for the owner, the group and everyone else. 666 = 6 / 6 / 6, so the owner, the group and everyone else can read and write (rw-rw-rw-).

Should I use 666 for files or for folders?

666 suits files. A folder needs execute before anyone can open it, so folders usually get 755 (or 775 when your group must write).

How do I set 666 in cPanel?

In File Manager, right-click the file or folder, choose Change Permissions, and tick the boxes so the number shows 666. Over SSH: chmod 666 path (add -R to include everything inside a folder).