A full-grown American Cocker Spaniel is a small to medium-sized dog and the smallest spaniel breed in the Sporting group. A full-grown American Cocker Spaniel typically stands between 14 to 15 inches at the shoulder, with males usually reaching 14 to 15 inches, while females are a bit smaller, between 13 to 14 inches. In terms of weight, males are typically between 19 to 36 pounds, and females range from 20 to 25 pounds.