Click through to find a larger image. Also, see the original list here. I’ve read 21 of the top 100, without ever considering myself a hardcore scifi/fantasy fan. How about you?
Titles I’d add, personally: Alas, Babylon; The Hunger Games; Harry Potter. But then, the latter two of these recommendations are children’s/YA, and this seems like a determinedly adult list.
flowchart of sci-fi