Adele told The Guardian's 1000 Songs Everyone Must Hear, that she finds it more difficult to write songs when she is in love and that this song, "is probably the only really nice song" on 19. She added, "There's nothing bad in that song, it's just about adoring someone. I wrote it when I was meant to be putting together songs for my album, but I couldn't because I was acting like an idiot, falling to pieces. You're like a fool when you're in love, you do things you shouldn't."
"Crazy for You" was written in the key of G Major. Adele played the guitar on the album version of "Crazy for You."