LessPass

LessPass is a stateless, open source password manager. Instead of storing credentials in an encrypted vault you must sync across devices, it derives each password from a master password, the site name, and a login. The same inputs always produce the same password, so you can regenerate any credential anywhere, remembering one master password.

You enter your login, master password, and site, and LessPass computes the password locally and copies it to the clipboard. Browser extensions for Chrome and Firefox open the generator on a focused password field. A command line tool installs through pip, and mobile apps cover iOS and Android. An optional server syncs saved site profiles.

LessPass is licensed under GNU GPLv3, with the mobile app also under the Mozilla Public License 2.0. The hosted server no longer accepts new registrations, so anyone wanting connected sync must self-host their own server. Its core idea is based on the Master Password app.