Hey, I hope someone can actually measure these for you and give you a more accurate answer. What I can say is that they are on the smaller side, particularly for Serengetis. I have 2 pair of these (in difdifferent colors) and several pair of other serengetis and countless other glasses. These are in the smaller frame category for all. They don't fit the face like the larger frame fashion glasses, which I also love, do. What I'd say is that they fit "normal" for an average/medium size face. They'd be pretty perfect for a small face and borderline annoying for a large face.
Hope that helps!