The Prairie Rattlesnake is a venomous pit viper exhibiting muted, earthy tones of greys and browns, camouflaging with dry landscapes. Adults typically measure between 1.5 to 3 feet in length.

This is a nominate subspecies, and it has one other subspecies called the Hopi Rattlesnake (Crotalus viridis nuntius). It is smaller, growing only up to 2 feet. Its name is derived from the Native American Hopi tribe, which lives in the habitat where the snakes live.