Stegosaurus Size Comparison
Stegosaurus was about 9 m long, stood about 2.5 m at the hip, and weighed about 3.5-5 tonnes as a large adult - roughly five times a person end to end, with a hip line above a 1.8 m person's head and kite-shaped plates rising higher still. The Stegosaurus 3D Viewer puts that person on screen next to the animal.
Stegosaurus published figures
These are real published measures for Stegosaurus, with a range where sources disagree:
| Measure | Figure | Vs a 1.8 m person |
|---|---|---|
| Length | about 9 m (NHM); related adult figures often about 6.5-9 m | ~5x a person end-to-end at the 9 m figure |
| Hip height | about 2.5 m (plates rise taller) | ~1.4x adult standing height |
| Weight | about 3.5-5 tonnes for large adults; Sophie (NHM young adult) about 1.6 tonnes | adult mass given as a range, not a single invented midpoint |
| When it lived | 152-145 million years ago | Late Jurassic; herbivore; genus Marsh 1877; S. stenops 1887, Colorado |
What the Stegosaurus facts panel shows
The facts panel beside the Stegosaurus canvas carries five rows and no more: Length 9 m, Weight 4.0 t, When it lived 152-145 Mya (Late Jurassic), Diet Herbivore, and Described - genus named by Marsh 1877; S. stenops named 1887, Colorado. Two figures in the table above are page copy rather than panel rows: the about 2.5 m hip height, and the 3.5-5 tonne adult range that the panel rounds to a single 4.0 t entry. Reading the two side by side is the point - the panel gives one number per row, this page gives the spread behind it.
How the Size vs human toggle scales the person
Tap Size vs human under the canvas and a 1.8 m figure appears beside the animal; the button then reads Hide human, so the same tap puts it away. The scale is derived from length alone: the scene draws Stegosaurus at a fixed 12 world units, so the viewer divides 12 by the 9 m published length and scales the person by that same units-per-metre factor. Nothing is stretched to make the gap look bigger, and the hip figure plays no part in the maths - the person is simply the same scene scale as the animal.
What a person would see beside a Stegosaurus
A person standing beside Stegosaurus would face a plated back rising well above their own head: at about 2.5 m at the hip, the hip line clears a 1.8 m person, and the double row of kite-shaped plates along the spine rises taller again. From snout to spiked thagomizer the animal spans about 9 m. Turn on the person in the viewer and orbit beside a hind leg to feel how far the plated back towers past the scale figure.
The viewer paints a rough Stegosaurus first, then swaps in a published model
What appears on first paint is a procedural Stegosaurus assembled in the browser - a double row of kite plates and a spiked thagomizer tail - so the scene is usable immediately. After that first paint the page fetches a published model, stegosaurus.glb (about 423 KB, CC0 1.0, by Quaternius via Poly Pizza), checks it against the asset manifest, caches it in the browser, and swaps it in; the status line then reads that it is showing a real 3D model of this species. If the fetch, the check, or WebGL fails, the procedural Stegosaurus simply stays on screen and the facts panel keeps working. Either way, skin and colour are an artistic reconstruction - fossils preserve bone, not soft covering.
Browser viewer, phone AR, and museum compared
The size figures above are available in three different ways, and the trade-offs are not subtle. These rows compare what the Stegosaurus viewer actually ships against a typical phone AR app, 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; the 3D engine is about 0.7 MB once, then cached | Often 50 to 500 MB store download | Travel time; or 0 MB for a photo |
| Time to first view | Seconds - one page load; the engine loads after paint | Minutes - install, permissions, tracking setup | Hours for a visit; instant for a photo |
| Place it 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 - any current browser with WebGL | Usually no | Photo yes; museum no |
| Published figures on hand | Yes - the five-row panel plus the table above | Varies by app | Labels vary; a photo rarely carries the full sheet |
| Reconstruction honesty | Artistic skin and colour; plate and thagomizer function left open | Often sells one settled plate story | Bones are real; colour still interpretive |
Nothing about a visit to the Stegosaurus viewer is uploaded to a server, which is what makes it workable on a classroom laptop or for a quick desktop check of Late Jurassic figures.
When a phone AR app or a museum fits better
A phone AR app wins when the point is the silhouette standing on your own floor at true scale; the Stegosaurus viewer never claims room placement. A museum wins for walking beside mounted Stegosaurus bone and feeling hall-scale presence that no screen matches. A static image wins only when a single shareable frame is enough and interactivity is not needed. The browser viewer wins on everything in between - no install, seconds to first view, works on a desktop, and the published numbers sit next to the model.
What these Stegosaurus size numbers are not
These figures are not a single settled measurement: they are published estimates carrying an honest adult mass range, which is why the table shows a spread instead of one confident number. Plate and thagomizer function - display, defence, thermoregulation - is not settled as one use, and this page does not pick a winner. The comparison table above is a trade-off sheet for the shipped viewer, not a ranking of commercial AR brands, and it does not claim AR features the page does not have. For the control walkthrough, see how to view Stegosaurus in 3D.
Other dinosaurs to compare
Other dinosaurs in the collection make useful size comparisons too: Stegosaurus is a shorter, plated herbivore, so for a much longer sail-backed predator, see the Spinosaurus 3D Viewer, or for a horned quadruped herbivore of similar length, see the Triceratops 3D Viewer.
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