Allosaurus
Order: Saurischia · Suborder: Theropoda · Infraorder: Tetanurae · Family: Allosauridae
Allosaurus is one of the best known carnosaurs. Sixty individuals, from juveniles to adults, were found at one site in Utah. It is likely that Allosaurus may have been the most common carnosaur of the Late Jurassic. Despite its size, Allosaurus is thought to have been a speedy hunter, running with a 3.7-meter-long stride at up to 20 mph. Its most distinguishing characteristic is the presence of two short horns, above and in front of each eye.
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Reference background: Natural History Museum, London — Dinosaurs; Smithsonian National Museum of Natural History — Dinosaurs; American Museum of Natural History — Dinosaurs & Fossils. Figures are typical published ranges; taxonomy follows the source era and modern consensus is noted where it differs. See our sources & fact-check policy.
Frequently asked questions
What does Allosaurus mean?
The name Allosaurus means “Other Lizard”. It is pronounced AL-uh-SAWR-us.
When did Allosaurus live?
Allosaurus lived during the Late Jurassic.
Was Allosaurus a carnivore or a herbivore?
Allosaurus was a carnivore.
How big was Allosaurus?
Allosaurus was about 40 feet (12.2 meters) long, around 17 feet (5.2 meters) tall, weighing up to 4,000 lbs (1,814 kg).
Related dinosaurs
Other dinosaurs from the Allosauridae family.
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