A gem to help you make sure that passwords are good, and not likely to be guessed or hacked, as suggested by NIST SP-800-63B.

Unpwn checks passwords locally against the top one million passwords, as provided by the nbp project. Then, it uses the haveibeenpwned API to check proposed passwords against the largest corpus of publicly dumped passwords in the world.

Inspired by @codahale's passpol, and uses prior work from nbp and devise-pwned_password.


Add unpwn to your Gemfile:

gem "unpwn", "~> 1.0"


require "unpwn"# Default length requirement is 8 characters minimum, no maximum

Unpwn.acceptable?("abc123") # => false
# Min and max can be set manually, but only as low as 8 and 64 respectively.
Unpwn.new(min: 10, max: 64).acceptable?("visit raven follow disk") # => true


After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.


Bug reports and pull requests are welcome on GitHub at https://github.com/indirect/unpwn. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.


The gem is available as open source under the terms of the MIT License.

Code of Conduct

Everyone interacting in the Unpwn project’s codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.