A Tyrannosaurus rex stood about 15 to 20 feet tall, or 4.6 to 6 meters high. Its length was about 40 feet, or 12 meters.
The Tyrannosaurus rex became extinct about 65 million years ago, but fossils have given researchers enough indicators for them to theorize that the Tyrannosaurus rex was among the largest carnivorous dinosaurs. Its jaw alone measured 4 feet long, or 1.2 meters, and was used to annihilate the bones of its prey. The dinosaur's skull, at 5 feet long or 1.5 meters, could mash into prey. However, its forearms, while long enough to catch some prey, could not reach its mouth.