The password.es website, including the password generation javascript. All password generation happens in the browser.
This website has an accompanying chrome extension, found at https://chrome.google.com/webstore/detail/passwordes-chrome/goamldkmlbmnbheldgfekanipnfefkgp whose source can be found at https://github.com/dcarrero/password.es-chrome
Based in passwds.ninja source code.