---
name: "mkpasswd-expect"
section: "1"
platform: "linux"
package: "expect"
version: "5.45.4-5"
release: "Arch Linux 2026-11-01"
platforms: ["linux"]
url: "https://new.carta.tech/mkpasswd-expect"
---

# mkpasswd-expect(1)

generate new password, optionally apply it to a user

## NAME

mkpasswd - generate new password, optionally apply it to a user

## SYNOPSIS

**mkpasswd** *\[* *args* \] \[ *user* \]

## INTRODUCTION

**mkpasswd** generates passwords and can apply them automatically to users. mkpasswd is based on the code from Chapter 23 of the O'Reilly book "Exploring Expect".

## USAGE

With no arguments, **mkpasswd** returns a new password.

	mkpasswd

With a user name, **mkpasswd** assigns a new password to the user.

	mkpasswd don

The passwords are randomly generated according to the flags below.

## FLAGS

The **-l** flag defines the length of the password.  The default is 9.   The following example creates a 20 character password.

	mkpasswd -l 20

The **-d** flag defines the minimum number of digits that must be in the password. The default is 2.  The following example creates a password with at least 3 digits.

	mkpasswd -d 3

The **-c** flag defines the minimum number of lowercase alphabetic characters that must be in the password. The default is 2.

The **-C** flag defines the minimum number of uppercase alphabetic characters that must be in the password. The default is 2.

The **-s** flag defines the minimum number of special characters that must be in the password. The default is 1.

The **-p** flag names a program to set the password. By default, /etc/yppasswd is used if present, otherwise /bin/passwd is used.

The **-2** flag causes characters to be chosen so that they alternate between right and left hands (qwerty-style), making it harder for anyone watching passwords being entered.  This can also make it easier for a password-guessing program.

The **-v** flag causes the password-setting interaction to be visible. By default, it is suppressed.

## EXAMPLE

The following example creates a 15-character password that contains at least 3 digits and 5 uppercase characters.

	mkpasswd -l 15 -d 3 -C 5

## SEE ALSO

*"Exploring Expect: A Tcl-Based Toolkit for Automating Interactive Programs"* by Don Libes, O'Reilly and Associates, January 1995.

## AUTHOR

Don Libes, National Institute of Standards and Technology

**mkpasswd** is in the public domain. NIST and I would appreciate credit if this program or parts of it are used.