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How large was an adult Tyrannosaurus rex?

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Sue, a dinosaur fossil (Tyrannosaurus rex) — tyrannosaur The fossilized remains of Sue, the most complete *Tyrannosaurus rex* skeleton in the world, on display at the Field Museum of Natural History, Chicago.

Large adult Tyrannosaurus rex specimens were massive predators, typically measuring more than 12 meters (about 39 feet) in length and weighing between 4,000 and 7,000 kg (about 9,000 to 15,000 pounds).123

While their height would have exceeded 6.5 meters (21 feet) if they stood in an upright posture, T. rex typically maintained a horizontal stance with its body parallel to the ground, resulting in a hip height of approximately 3.6 to 3.9 meters (12 to 13 feet). Notable specimens demonstrate the upper limits of these dimensions:23
* "Sue": Measures 12.8 meters (42 feet) in length.23
* "Scotty": Estimated at 13 meters (42.7 feet) long with a weight of 8,870 kg (19,555 pounds).23

These dinosaurs reached their full adult size in less than 20 years.43