Buttercup is a free cross platform open source password manager for Windows, Linux, macOS and iOS and Android mobile platforms. And it is also available as a browser extensions for Chrome and Firefox. Using Buttercup, you can store your important password credentials easily and securely. It uses very strong 2AES 256bit CBC mode with a SHA256 HMAC encryption to protect your passwords under a single master password. And it will sync across all your devices. You just need to remember your master password only.
You passwords are stored in a secure archive, which can then be stored on your own computer or any other Dropbox, Google Drive, ownCloud, Nextcloud, WebDAV like cloud services that is based on you. You choose where the password vault is stored. Complete control of all things.
Buttercup comes with some basic merge conflict resolution for user safty. It avoid when 2 changes are made at once on the file , locally or remote. It supports import passwords from other popular password managers like Password, Lastpass and KeePass. It also comes with easy to use buil in password generator for create random strong password.You can also export your passwords as in CSV format. It is released under GNU/GPL Version 3 open source licence.
For Windows it is available as exe format, Mac OS as dmg and Linux as deb, rpm, tarball, AppImage format.