Popped nearly all of the kernels. It was kind of loud so make sure to pop your popcorn before the movie starts. I will say, before this we had a silicon microwave popper. The popcorn would sometimes burn. That doesn’t happen with this popper. However, the popcorn in this one is a bit “chewier” than that made in tue silicone one. But that’s just science: air-popped popcorn is chewier because it keeps a little more water inside, while the microwave popcorn loses more water and gets crispier.