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A field guide to one very famous dinosaur

Tyrannosaurus rex, bone by bone.

Banana-sized teeth, arms that still puzzle scientists, a skeleton found thanks to a flat tyre and a name that won by a single page. Every fact traced to a source, plus games, printables and an eraser called Useless who has been handed a hard hat.

Meet T. rex The big facts page

A mounted T. rex skeleton lunging forward with its jaws open, in the Smithsonian’s dinosaur hall
A T. rex skeleton in the dinosaur hall at the Smithsonian’s National Museum of Natural History.Photo: John Gibbons, Smithsonian (shared by USDA), Public domain, Commons
1905the year Henry Fairfield Osborn named it Wikipedia: Tyrannosaurus
69–66million years ago: when its fossils date from Wikipedia: Tyrannosaurus
30.5 cmthe biggest T. rex tooth found so far, root included Wikipedia: Tyrannosaurus · checked 24 Oct 2026
2clawed fingers on each tiny hand Wikipedia: Tyrannosaurus

The short version

Tyrannosaurus rex was named in 1905 by Henry Fairfield Osborn, president of the American Museum of Natural History. Wikipedia: Tyrannosaurus The name means “tyrant lizard king”: tyrannos is Greek for tyrant, sauros is Greek for lizard, and rex is Latin for king. Wikipedia: Tyrannosaurus

Its fossils come from rocks dated to the end of the Cretaceous period, 69 to 66 million years ago. Wikipedia: Tyrannosaurus It lived in what is now western North America, which was then an island continent called Laramidia. Wikipedia: Tyrannosaurus

T. rex was a theropod: a two-legged meat-eater, with a massive skull balanced by a long, heavy tail. Wikipedia: Tyrannosaurus It was one of the last non-avian dinosaurs, living right up to the mass extinction 66 million years ago. Wikipedia: Tyrannosaurus

And it is still surprising people. In July 2026, scientists described a foot bone from a hatchling T. rex, estimated at about 75 cm long and 2.5 kg. Wikipedia: Tyrannosaurus · checked 24 Oct 2026

A 1919 painting of a T. rex standing upright in a green landscape, with a duck-billed dinosaur nearby
Charles R. Knight’s 1919 painting shows the old upright pose. Today we know T. rex held its body level.Art: Charles R. Knight, 1919, Public domain, Commons

Start digging

Skull, teeth & tiny armsBone-crushing jaws, “lethal banana” teeth and two-fingered hands. How it livedGrowth spurts, senses, speed and what was on the menu. How it was discoveredFrom a lone tooth in 1874 to the name that won by one page. Famous fossilsSue, Stan, Scotty, Bucky and the Wankel rex. Its world & the asteroidHell Creek, its neighbours and the end of the Cretaceous. Myths vs factsTail-dragging, scavenging, and “it couldn’t see you if you stood still”.

Tile images are credited on their pages and on the credits page.

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Found because of a flat tyre

Sue was found on 12 August 1990 by fossil hunter Sue Hendrickson, and is named after her. Wikipedia: Sue (dinosaur) The find happened because of a flat tyre: while the rest of the team went to get the truck fixed, Hendrickson explored some nearby cliffs. Wikipedia: Sue (dinosaur)

And named by a single page

T. rex won because its name appeared one page earlier than Dynamosaurus in Osborn’s 1905 paper. If the pages had been the other way round, it would be called Dynamosaurus. Wikipedia: Specimens of Tyrannosaurus The whole story is on the discovery page.

The long skeleton of Sue the T. rex on display in a museum hall, with visitors walking past
Sue at the Field Museum in Chicago, photographed in 2005.Photo: Shoffman11, Public domain, Commons
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Free sample

Free T. rex printables sample, 7 pages. Pick your paper size:

A4 1.0 MBUS Letter 1.0 MB

T. rex printables

Fact-checked PDFs in A4 and US Letter.

  • T. rex Fossil Explorer Action Pack

    Set up a dig site, map it, log your finds, do footprint maths, then a quiz and certificate

    $5.99

  • T. rex Anatomy & Life Cycle Worksheets

    Label the T. rex, skull and teeth, tiny arms, growing up, size maths and a quiz, with answer keys

    $4.99

  • T. rex & Friends Dinosaur ID Cards

    Twelve double-sided photo cards: T. rex, Sue, Triceratops and more, plus Who am I? and a deep-time sort

    $4.49

  • T. rex Activity & Colouring Pack

    Colouring scenes, mazes and puzzles for ages 4 to 9

    $3.99

  • T. rex Facts Poster Set

    Seven fact-checked posters, from banana teeth to myths vs facts

    $3.99

  • Fossil Hunter’s Field Journal & Finds Log

    Find record cards, a finds log, sketch pages, museum visit logs and a fossil hunter’s code

    $3.49
Best value

The Complete T. rex Printables Bundle

All six packs plus a guide, A4 and US Letter. Everything above in one download.

$12.99