The weight of a rattlesnake depends upon the species, the age of the animal and the health of the animal. A new-born pygmy rattlesnake weighs only a few grams. The eastern diamondback rattlesnake is the largest of the rattlers. The heaviest eastern diamondback rattlesnake ever found weighed 15.4 kg (34 Ib), and was 7.8 ft (2.4 m) long.