Dimensions
| Measurement | Metric | Imperial | Notes | Source |
|---|---|---|---|---|
| Length (typical adult) | ≈ 12 m | ≈ 39 ft | Estimated; nose to tail tip of a normal adult. Approximate | [1] |
| Length (largest specimens) | up to 13 m | up to 43 ft | Estimated; the NHM says Sue and Scotty were almost 13 m long in life, and the Field Museum gives Sue as more than 40 ft. Maximum | [1] [2] |
| Height at the hips | 3.5–4 m | 11–13 ft | Estimated hip height of an adult; Sue stands 13 ft at the hip. Range: varies | [1] [2] |
| Mass (typical adult) | 5,000–7,000 kg | 5.5–7.7 US tons | Estimated weight of a normal adult. Range: varies | [1] |
| Mass (largest specimens) | at least 8,000 kg | at least 8.8 US tons | Estimated; the NHM says Sue and Scotty weighed over 8,000 kg in life. Approximate | [1] |
| Skull length (largest) | at least 1.5 m | at least 4 ft 11 in | Some of the largest T. rex skulls are over 1.5 m long. Approximate | [1] |
About the Tyrannosaurus rex
Tyrannosaurus rex was a large meat-eating dinosaur that lived in what is now the western United States and Canada at the very end of the Cretaceous, about 68 to 66 million years ago. London's Natural History Museum estimates a typical adult at about 12 metres long and 3.5 to 4 metres tall at the hips, weighing roughly 5 to 7 tonnes. The biggest known skeletons, Sue and Scotty, came from animals nearly 13 metres long and over 8 tonnes.
- Sue, at the Field Museum in Chicago, is the largest and most complete T. rex skeleton found, at around 90 percent complete, and lived to about 28 years old. [2]
- Barnum Brown found the first known T. rex skeletons in 1900 and 1902, and Henry Fairfield Osborn named the species in 1905. [1]
- Tooth marks show T. rex fed on Triceratops and Edmontosaurus, and bone fragments turn up in its fossilised dung. [1]
How many fit?
- ≈ 7.1 × Human · height lined up end to end match the Tyrannosaurus rex · length (typical adult)
- ≈ 55–90 × Human · body mass on the scales weigh as much as Tyrannosaurus rex · mass (typical adult)
- ≈ 2.4 × Car · length lined up end to end match the Tyrannosaurus rex · length (typical adult)
- ≈ 3–4.3 × Car · curb weight on the scales weigh as much as Tyrannosaurus rex · mass (typical adult)
Counts divide one sourced figure by another. "End to end" uses each object's main measurement; weight and volume rows appear only when both figures are sourced.
How it compares
- 7.1× A Tyrannosaurus rex is about 7.1 times as long as an average adult is tall. See side by side
- 2.4× A Tyrannosaurus rex is about 2.4 times as long as a mid-size car. See side by side
- 1/1 A Tyrannosaurus rex is about as long as a typical new house is wide. See side by side
- 1× A Tyrannosaurus rex is about as long as a Brachiosaurus is tall. See side by side
- 1/2 A tennis court is about 2 times as long as a Tyrannosaurus rex. See side by side
- 1/3.3 A Boeing 737 is about 3.3 times as long as a Tyrannosaurus rex. See side by side
Factors compare the length (typical adult) of a Tyrannosaurus rex with each object’s own main measurement (height for a human). Where a size varies, the factor is given as a range.
Notes on these figures
- All sizes are estimated from fossil skeletons; body mass in particular varies a lot between studies.
- Size varied between individuals, and most T. rex were probably smaller than the record specimens.
Sources
- Natural History Museum, London, Dino Directory: Tyrannosaurus. Accessed 25 September 2026.
- Field Museum, SUE the T. rex. Accessed 25 September 2026.