Although the sizes of the titanosaurs varied greatly, the largest dinosaurs known belong to this group, which includes Dreadnoughtus, Patagotitan, and Argentinosaurus. Dreadnoughtus was the longest, measuring 26 metres (about 85 feet) long; however, it weighed less than Patagotitan and Argentinosaurus, whose weights have been estimated at 63.5 metric tons (70 tons) and 70 metric tons (77 tons), respectively.