chmod 424 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

424

Symbolic

r---w-r--

Binary

100 010 100

Risk Level

Moderate

Summary: chmod 424 gives the owner read, the group write, and everyone else read.

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

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

Octal

Symbolic

Target File / Path

-R Recursive -v Verbose

424

r---w-r--

Owner: read · Group: write · Others: read

chmod 424 filename

Moderate Every member of the group can modify this file.

View the full chmod 424 guide →

chmod 424 Breakdown

Class	Digit	Symbolic	On a file	On a directory
Owner (u)	`4`	`r--`	Read only	Can list names, but not enter
Group (g)	`2`	`-w-`	Write only (rarely useful)	No practical effect without x
Others (o)	`4`	`r--`	Read only	Can list names, but not enter

Is chmod 424 Safe?

Moderate

Every member of the group can modify this file.
Any user can read this file — never use it for secrets such as keys or .env files.
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

424 is uncommon in standard Linux setups. The closest widely used permission is chmod 400.

chmod 424 Command Examples

# Apply using octal mode
chmod 424 filename

# Apply using equivalent symbolic mode
chmod u=r,g=w,o=r filename

# Recursive command warning:
chmod -R 424 /path/to/dir
# Note: -R applies the same mode to files and directories. Use find to treat them separately:
find /path/to/dir -type f -exec chmod 424 {} +

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

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

umask Relationship

A umask of 353 makes new directories 424 and new files 424. Test umask values with our interactive Umask Calculator.

Frequently Asked Questions

What does chmod 424 mean?

chmod 424 gives the owner read, the group write, and everyone else read. In octal notation, the owner receives 4 (read), the group receives 2 (write), and others receive 4 (read).

Is chmod 424 safe?

chmod 424 is classified as Moderate. Every member of the group can modify this file.

What is chmod 424 in symbolic notation?

In symbolic notation, chmod 424 is represented as r---w-r--. You can apply this permission using the equivalent symbolic command "chmod u=r,g=w,o=r filename".

Related Permissions

Change one bit:

chmod 024 remove owner read chmod 624 add owner write chmod 524 add owner execute chmod 464 add group read chmod 404 remove group write chmod 434 add group execute chmod 420 remove others read chmod 426 add others write chmod 425 add others execute

← chmod 423 chmod 425 →

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