WordPress.org

Forces all users to have a strong password when they're changing it on their profile page. If user enters a weak password an error message is displayed.

It uses the same algorithm to determine password strength as WordPress.

On multisite, network administrator can define required password strength (Network Admin --> Settings --> Enforce Strong Passwords). On single site it's admin has this capability (Options --> Enforce Strong Passwords).

Developed for private use, but has perspective for more extensive usage. I can't guarantee any support in the future nor further development, but it is to be expected. Kindly inform me about bugs, if you find any, or propose new features: zaantar@zaantar.eu.