Dimensions
| Measurement | Metric | Imperial | Notes | Source |
|---|---|---|---|---|
| Length (estimated) | ≈ 9 m | ≈ 30 ft | Estimated nose-to-tail length; Britannica says body length approached 9 m (30 ft). Approximate | [1] [2] |
| Length range (AMNH estimate) | 6–8.5 m | 20–28 ft | Estimated length of Triceratops horridus; AMNH gives 6 to 8.5 meters (20 to 28 feet). Range: varies | [3] |
| Mass (estimated) | ≈ 10,000 kg | ≈ 11 US tons | Estimated body weight. Approximate | [1] |
| Mass of the largest adults (Britannica estimate) | 5,450–7,260 kg | 6.01–8 US tons | Estimated weight of the largest adults; Britannica also gives about 12,000-16,000 pounds. Range: varies | [2] |
| Skull length (largest) | up to 3 m | up to 9 ft 10 in | Some individuals had skulls nearly 3 m (about 10 ft) long. Maximum | [2] |
About the Triceratops
Triceratops was a large, four-legged, plant-eating dinosaur with three horns, a parrot-like beak and a bony frill at the back of its skull. It lived in western North America at the very end of the Cretaceous, about 68 to 66 million years ago, and was one of the last non-bird dinosaurs. The Natural History Museum, London estimates it at about 9 metres long and 10,000 kg, while other museum estimates are smaller.
- Its frill could reach nearly one metre across, and its skull is one of the largest of any land animal. [1]
- A partial Triceratops fossil collected in 1997 has a horn bitten off by Tyrannosaurus that later healed, showing the animal survived the attack. [1]
- Othniel Charles Marsh first found Triceratops horn cores in 1887 and at first thought they came from a giant bison. [1]
- Triceratops is the most commonly found dinosaur in the uppermost Cretaceous rocks of western North America, but it is rarely found in groups. [2]
How many fit?
- ≈ 5.4 × Human · height lined up end to end match the Triceratops · length (estimated)
- ≈ 120 × Human · body mass on the scales weigh as much as Triceratops · mass (estimated)
- ≈ 7.9 × African lion · shoulder height lined up end to end match the Triceratops · length (estimated)
- ≈ 44–82 × African lion · body mass on the scales weigh as much as Triceratops · mass (estimated)
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
- 5.4× A Triceratops is about 5.4 times as long as an average adult is tall. See side by side
- 7.9× A Triceratops is about 7.9 times as long as an African lion is tall at the shoulder. See side by side
- 1.8× A Triceratops is about 1.8 times as long as a mid-size car. See side by side
- 1/1.2 A school bus is about 1.2 times as long as a Triceratops. See side by side
- 1/1.3 A Brachiosaurus is about 1.3 times as tall as a Triceratops is long. See side by side
- 1/2.6 A tennis court is about 2.6 times as long as a Triceratops. See side by side
Factors compare the length (estimated) of a Triceratops 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 estimates from fossils.
- Mass estimates differ: the Natural History Museum gives 10,000 kg, while Britannica puts the largest adults at 5,450-7,260 kg.
- The AMNH card gives a smaller length range (6 to 8.5 m) than the Natural History Museum's 9 m.
Sources
- Natural History Museum, London, Triceratops (Dino Directory). Accessed 25 September 2026.
- Encyclopaedia Britannica, Triceratops. Accessed 25 September 2026.
- American Museum of Natural History, Triceratops horridus (OLogy card 010). Accessed 25 September 2026.