specimen BYU 9024 might have been even larger reaching lengths of 45 - 48 m.Others, like the brachiosaurids, were extremely tall, with high shoulders and extremely long necks. The tallest sauropod was the giant Barosaurus specimen at 22 m tall. By comparison, the giraffe, the tallest of all living land animals, is only 4.8 to 5.6 m tall.

The best evidence indicates that the most massive were Argentinosaurus (), ''Mamenchisaurus sinocanadorum''