The largemouth is an olive green fish, marked by a series of dark, sometimes black, forming a jagged horizontal stripe along each side. The upper jaw (maxilla) of a largemouth bass extends beyond the rear margin of the eye. In comparison to age, a female bass is larger than a male. The largemouth is the largest of the black basses. The largest reached a maximum recorded overall length of and a maximum unofficial weight of . The fish lives 16 years on average.