How Does Spotify Know You So Well?

A software engineer explains the science behind personalized music recommendations

Sophia Ciocca
9 min readOct 10, 2017
Photo by studioEAST/Getty Images

This Monday — just like every Monday before it — over 100 million Spotify users found a fresh new playlist waiting for them called Discover Weekly. It’s a custom mixtape of 30 songs they’ve never listened to before but will probably love, and it’s pretty much magic.

I’m a huge fan of Spotify, and particularly Discover Weekly. Why? It makes me feel seen. It knows my musical tastes better than any person in my entire life ever has, and I’m consistently delighted by how satisfyingly just right it is every week, with tracks I probably would never have found myself or known I would like.

For those of you who live under a soundproof rock, let me introduce you to my virtual best friend:

A Spotify Discover Weekly playlist — specifically, mine.

As it turns out, I’m not alone in my obsession with Discover Weekly. The user base goes crazy for it, which has driven Spotify to rethink its focus, and invest more resources into algorithm-based playlists.



Sophia Ciocca

Warrior for authenticity. Uncovering my truest self & documenting the journey.