According to the Defenders of Wildlife website, the average weight of an adult gorilla ranges between 200 and 450 pounds, depending on sex. Male gorillas tend to be much larger, on average, than females.
Variation in male weights potentially varies by 150 pounds between the largest and smallest males, but even the smallest male gorillas are 300 pounds or more. Females, on the other hand, weigh around 200 pounds with a smaller range in weight between them. LiveScience claims a top weight of 480 pounds for male gorillas, depending on subspecies, and a top weight for females of 215 pounds. LiveScience also claims that gorillas are the world's largest primates.