chmod 561 Permission Explained

Notice: This is an unusual permission set: some classes have more access than the class above them. It is rarely correct in practice.

Octal

561

Symbolic

r-xrw---x

Binary

101 110 001

Risk Level

Moderate

Summary: chmod 561 gives the owner read/execute, the group read/write, and everyone else execute.

Class	Read (4)	Write (2)	Execute (1)	Octal
Owner (u)				5
Group (g)				6
Others (o)				1

setuid (4) setgid (2) sticky bit (1)

Octal

Symbolic

Target File / Path

-R Recursive -v Verbose

561

r-xrw---x

Owner: read/execute · Group: read/write · Others: execute

chmod 561 filename

Moderate Every member of the group can modify this file.

View the full chmod 561 guide →

chmod 561 Breakdown

Class	Digit	Symbolic	On a file	On a directory
Owner (u)	`5`	`r-x`	Read and execute	Can list and enter
Group (g)	`6`	`rw-`	Read and write	Can list names, cannot enter
Others (o)	`1`	`--x`	Execute only	Can enter (cd) but not list contents

Is chmod 561 Safe?

Moderate

Every member of the group can modify this file.
Even the owner cannot modify this file without changing permissions first.
Unusual: a lower class has permissions the class above it lacks.

Common Use Cases

561 is uncommon in standard Linux setups. The closest widely used permission is chmod 775.

chmod 561 Command Examples

# Apply using octal mode
chmod 561 filename

# Apply using equivalent symbolic mode
chmod u=rx,g=rw,o=x filename

# Recursive command warning:
chmod -R 561 /path/to/dir
# Note: -R applies the same mode to files and directories. Use find to treat them separately:
find /path/to/dir -type d -exec chmod 561 {} +

# Verify permissions
stat -c '%a %A %n' filename    # Linux
stat -f '%Lp %Sp %N' filename   # macOS

# Example ls -l output:
-r-xrw---x 1 alice staff 1024 Jan 15 10:00 example.txt

umask Relationship

A umask of 216 makes new directories 561. Test umask values with our interactive Umask Calculator.

Frequently Asked Questions

What does chmod 561 mean?

chmod 561 gives the owner read/execute, the group read/write, and everyone else execute. In octal notation, the owner receives 5 (read/execute), the group receives 6 (read/write), and others receive 1 (execute).

Is chmod 561 safe?

chmod 561 is classified as Moderate. Every member of the group can modify this file.

What is chmod 561 in symbolic notation?

In symbolic notation, chmod 561 is represented as r-xrw---x. You can apply this permission using the equivalent symbolic command "chmod u=rx,g=rw,o=x filename".