chmod calculator

Turn file permissions into numbers and back, and get the command to run.

Processed on your device, never uploaded

Permissions

Common

Read

Write

Run

Owner

Group

Everyone

SpecialsetuidRun as the file’s ownersetgidRun as the file’s group, or keep the folder’s groupSticky bitIn a folder, only owners can delete their files

Result

Commandchmod 644 filechmod u=rw,g=r,o=r file

Octal

Symbolic

Owner can read and change it. Group can only read it. Everyone else can only read it.

Who can do what

	Read	Write	Run
Owner	Yes	Yes	No
Group	Yes	No	No
Others	Yes	No	No

644 is rw-r--r--.

Processed on your device, never uploaded

Command

File or folder

Include everything inside (-R)

What it does

The chmod calculator turns file permissions into the numbers and letters Unix and Linux use. Tick read, write and run for owner, group and others, with setuid, setgid and the sticky bit if you need them, and see the octal form like 755, the symbolic form like rwxr-xr-x and the ready chmod command. Type either form and the boxes follow.

How to use it

1Tick the permissions, or type a mode like 644 or rwxr-xr-x.
2Check the table of who can do what.
3Copy the chmod command.

Questions

What should I use for a normal file?

644 for files and 755 for programs and folders. Use 600 for private keys.

Why is 777 a bad idea?

It lets every user on the machine change the file. Almost nothing needs it.

What are setuid and setgid?

They run a program with the rights of its owner or group. Use them only on programs you trust.