Personally, I’ll be going with C major, because of two small details. First, the song ends on a C chord, which gives us a clue as to how the writer hears the song. Next, Halsey is singing “blue notes” from the C blues scale, which is something you can trust. But because the melody notes and loop notes make an A minor chord in first inversion, you could also hear that as an Am chord, and so an A minor tonality. Boosted posts on Facebook are great for targeting the right audience, in the right location, with ads that show up organically in their feed. Learn about how to work with the ever-changing Facebook visibility algorithms in this article.