chmod 444 Permission Explained: Read-Only for Everyone

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

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

Octal

Symbolic

Target File / Path

-R Recursive -v Verbose

444

r--r--r--

Owner: read · Group: read · Others: read

chmod 444 filename Copy

Low Risk Any user can read this file — never use it for secrets such as keys or .env files.

View the full chmod 444 guide →

chmod 444 Breakdown

Is chmod 444 Safe?

Low Risk

• 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.

When not to use it

• Private credentials and configuration files that require periodic updates

Common Use Cases

• Published read-only data files and reference documentation
• Software license notices and checksum verification files

chmod 444 Command Examples

# Apply using octal mode
chmod 444 filename

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

# Recursive command warning:
chmod -R 444 /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 444 {} +

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

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

umask Relationship

A umask of 333 makes new directories 444 and new files 444. Test umask values with our interactive Umask Calculator.

Frequently Asked Questions

Related Permissions

Change one bit:

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