Tyrannosaurus rex Size Comparison
Tyrannosaurus rex 3D Viewer puts published fossil figures beside a 1.8 m person on screen - length about 12.3 m, hip height about 3.7 m, weight about 8.9 tonnes. This page covers those numbers, the four controls that produce the comparison, and when a phone AR app or a museum serves you better.
Tyrannosaurus rex published figures
The Tyrannosaurus rex facts panel and this table use the same real published measures (ranges are not needed here - these are the values the viewer shows):
| Measure | Figure | Vs a 1.8 m person |
|---|---|---|
| Length | about 12.3 m | ~6.8x a person standing end-to-end |
| Hip height | about 3.7 m | ~2.1x adult standing height |
| Weight | about 8.9 tonnes | many times a human body mass |
| When it lived | 68-66 million years ago | Late Cretaceous |
| Teeth note | ~60 serrated teeth up to 20 cm | including the root |
How the Tyrannosaurus rex size-vs-human toggle stays honest
The Tyrannosaurus rex model is drawn to a fixed on-screen length so it fits the canvas; the Size vs human control then places a 1.8 m person at the true length ratio to that real ~12.3 m figure. Tap Size vs human under the canvas to show or hide the scale figure - the comparison is proportional, not a decorative sticker.
What a person would see beside a Tyrannosaurus rex
What a person would see is a hip joint towering overhead: at about 3.7 m at the hips, a Tyrannosaurus rex hip joint sits well above a 1.8 m person's head. From snout to tail the animal spans roughly 12.3 m - turn on the person in the viewer and stand the camera beside a hind leg to feel how far the back is above eye level.
The four Tyrannosaurus rex controls under the canvas
Open the Tyrannosaurus rex 3D Viewer and wait for the facts panel to fill. Once the status line offers drag to rotate and scroll or pinch to zoom, orbit the model with the pointer and zoom with the wheel or a two-finger pinch. Four controls sit under the canvas:
- Fullscreen - expands the wrapper, so the buttons stay visible beside the scene
- Stop rotation - freezes the auto-spin; the label flips to Auto-rotate while spinning is off
- Idle motion - adds a subtle hind-leg sway; tap again for Stand still
- Size vs human - shows the 1.8 m scale figure described above; the label flips to Hide human while it is on
The Tyrannosaurus rex facts panel and part clicks
Beyond the measures in the table above, the Tyrannosaurus rex facts panel carries the diet (carnivore) and the naming history: the first described skeleton came from a 1902 Montana find by Barnum Brown. A short click - not a drag - on the head, tail, or a leg swaps in a note for that part; click empty space to return to the fact sheet.
Where the browser viewer, a phone AR app, and a museum each fit
The Tyrannosaurus rex viewer loads in the browser with about 0.7 MB of WebGL once cached, no account, and no room-scale AR. These rows compare what it actually ships against typical phone AR dinosaur apps, a museum hall visit, and a still photo:
| Aspect | In-browser 3D viewer | Phone AR app | Museum / static image |
|---|---|---|---|
| Install / download | 0 MB app install; ~0.7 MB three.js cached after first load | Often 50 to 500 MB store download | Travel time; or 0 MB for a photo |
| Time to first view | Seconds - one page load | Minutes - install, permissions, tracking setup | Hours for a visit; instant for a photo |
| Place in a physical room | No - orbit on a flat screen only | Yes - true AR placement when tracking works | Hall scale in person; none in a photo |
| Desktop without a phone | Yes - current browser with WebGL | Usually no | Photo yes; museum no |
| Published size figures on hand | Yes - the full table above | Varies by app | Labels vary; photo rarely carries full sheet |
| Soft-tissue / color accuracy | Artistic reconstruction disclosure in the panel | Often stylized skins | Bones are real; color still interpretive |
Pick the browser viewer for drag-orbit, the scale figure, and part clicks with nothing to install: the engine loads after paint and then stays cached, which suits a classroom laptop or a quick desktop check of the Late Cretaceous numbers. A phone AR app wins when you need the silhouette standing on your living-room floor. A museum wins for walking beside mounted bone at hall scale, and a static image wins only when you need a single shareable frame with no interactivity.
What these Tyrannosaurus rex numbers are not
The figures are published bone-based estimates, and the skin color in the viewer is an artistic reconstruction - fossils preserve no color or soft tissue. The controls above cover the in-browser viewer only: it never places the model in your room, and it claims no soft-tissue accuracy. The comparison table is a trade-off sheet for the shipped viewer, not a ranking of commercial AR brands.
Other dinosaurs to compare
Other dinosaurs in the collection make useful size comparisons too: for another giant theropod near its own size, see the Spinosaurus 3D Viewer, or for its classic horned rival in the fossil record and in popular culture, see the Triceratops 3D Viewer.
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