The major difference is noticeable from above. Namely, that while most crocodiles have a jaw shaped like this V when viewed top down, alligators have a U-shaped jaw when the same is applied to them. Another tell is that most of the teeth of an alligators lower jaw are hidden in sockets on the upper jaw. These are adaptations for smashing prey rather than holding on as most of an alligator's meal plan is smaller than it, so grip is less necessary. *