ListenBrainz is described as 'open source music website that allows users to import their listen history. One of the goals is for this data to be used for building open music recommendation systems' and is a Music Discovery Service in the Audio & Music category. There are six alternatives to ListenBrainz, not only websites but also apps for a variety of platforms, including Android, Self-Hosted solutions, Mac and Windows. The best alternative is Last.fm, which is free. Other great sites and apps similar to ListenBrainz are Libre.fm (Free, Open Source), Maloja (Free, Open Source), MyRadio (Freemium) and Wavy.fm (Free).
Last.fm is a music community website that offers personalized internet radio, using a recommendation system called "Audioscrobbler" to build a detailed profile of users based on their music tastes and interests.
GNU FM is the music community platform created in 2009 for the GNU Project. It implements the Audioscrobbler protocol, powers libre.fm and supports federation between many Auidoscrobbler servers, including Last.fm.