The Number One Largest Dinosaur
Among the dinosaurs discovered so far, Argentinosaurus is the largest.
Argentinosaurus was a Saurischian - Sauropodomorph that lived in South America during the Late Cretaceous. Although only about 10 bones have been found so far, it is estimated to have been over 35 meters long and weighed over 90 tons based on the size of the discovered bones.
Seismosaurus was also a large dinosaur in the 30-meter class, but in 2004 it was determined that "the individual called Seismosaurus was not a separate genus but belonged to Diplodocus" (Seismosaurus is now considered an invalid name).
In 2014, there was news of the discovery of a 40-meter class sauropodomorph in Argentina, surpassing Argentinosaurus. It has not yet been given a scientific name, but it is presumed to be a member of the Titanosauria group.
The Largest Theropod (Carnivorous Dinosaur)
The largest among the theropods, which include carnivorous dinosaurs, is Spinosaurus.
This dinosaur, which lived in Africa, is estimated to have been 13 to 15 meters long and weighed 4 tons (it is known that Spinosaurus was piscivorous).
Other theropods in the 13-meter class include Giganotosaurus and Tyrannosaurus.
Giganotosaurus lived in South America during the Late Cretaceous. Tyrannosaurus weighed 6 tons, overpowering Spinosaurus in terms of weight.