passwd command

Change user password.

Overview

The passwd command allows users to change their own password or, for system administrators, to change or administer other users' passwords. It modifies the /etc/passwd and /etc/shadow files that store user account information and encrypted passwords.

Options

-d

Delete a user's password (make it empty). This option is restricted to root.

$ sudo passwd -d username
passwd: password expiry information changed.

-l

Lock the specified account by prefixing the encrypted password with an exclamation mark. This prevents the user from logging in.

$ sudo passwd -l username
passwd: password expiry information changed.

-u

Unlock a locked password by removing the exclamation mark prefix.

$ sudo passwd -u username
passwd: password expiry information changed.

-e

Expire a user's password, forcing them to change it at next login.

$ sudo passwd -e username
passwd: password expiry information changed.

-S

Display password status information for an account.

$ passwd -S username
username PS 2025-04-01 0 99999 7 -1

Usage Examples

Changing your own password

$ passwd
Changing password for user.
Current password: 
New password: 
Retype new password: 
passwd: all authentication tokens updated successfully.

Changing another user's password (as root)

$ sudo passwd username
New password: 
Retype new password: 
passwd: all authentication tokens updated successfully.

Locking and unlocking an account

$ sudo passwd -l username
passwd: password expiry information changed.
$ sudo passwd -u username
passwd: password expiry information changed.

Tips:

Password Complexity Requirements

Most systems enforce password complexity rules. A strong password typically needs to:

Check Password Status

Use passwd -S username to check if a password is locked, expired, or when it was last changed.

Password Files

The actual encrypted passwords are stored in /etc/shadow, not in /etc/passwd. The shadow file is only readable by root for security reasons.

Frequently Asked Questions

Q1. How do I change my own password?

A. Simply type passwd and follow the prompts to enter your current password and then your new password twice.

Q2. How can I force a user to change their password at next login?

A. Use sudo passwd -e username to expire a user's password.

Q3. What does "authentication token manipulation error" mean?

A. This usually indicates a system problem with the password files or insufficient permissions. Only root can change other users' passwords.

Q4. How do I create a user without a password?

A. First create the user with a normal password, then use sudo passwd -d username to delete the password.

References

https://man7.org/linux/man-pages/man1/passwd.1.html

Revisions