RandomBasis

Dinosaur to draw

Random Dinosaur Generator

Draw a random dinosaur with its period and diet - filter by Triassic, Jurassic or Cretaceous.

Runs locally in your browser. Nothing you generate is ever sent to a server.

Press "Generate Dinosaur" to see a result here.

Period or group

About this random dinosaur generator

Press Generate and a dinosaur comes up with the period it lived in and what it ate. The list covers all three periods of the Mesozoic, plus the flying and swimming reptiles that shared the world with them.

Pterosaurs and plesiosaurs are not dinosaurs

This is the single most common misconception about the subject, so they are grouped separately here rather than being quietly mixed in. Pterodactyls flew and plesiosaurs swam, but neither belongs to the dinosaur group - they were separate lines of reptile living at the same time. Mentioning this once usually fixes it permanently, which is why the filter names them for what they are.

The three periods

The Triassic has the earliest and generally smallest dinosaurs, the Jurassic has the enormous long-necked sauropods and the plated Stegosaurus, and the Cretaceous has most of the famous ones including Tyrannosaurus and Triceratops. Filtering by period is what makes this useful for a lesson on one slice of the Mesozoic rather than all of it at once.

Science that keeps moving

Details here follow the mainstream view, but palaeontology revises itself regularly. Spinosaurus has been reconstructed several different ways within living memory, and the debate about whether it swam is not settled. That uncertainty is worth telling children about rather than hiding - it is how science actually works.

Common uses

How the randomness works

The list is filtered to the group you chose, then one is drawn using your browser's cryptographic random source with rejection sampling, so nothing is favoured. Batches without repeats use a Fisher-Yates shuffle driven by the same source.

How do I get a random dinosaur?

Press Generate and one comes up with the period it lived in and what it ate.

Can I filter by period?

Yes. The filter covers the Triassic, Jurassic and Cretaceous, plus flying and marine reptiles.

Are pterosaurs and plesiosaurs dinosaurs?

No, and that is why they are in separate groups here. Pterosaurs flew and plesiosaurs swam, but neither belongs to the dinosaur group - they were reptiles living alongside them.

Can I draw a list for a project?

Yes. Set the quantity and press once, then Copy All to take the list with periods and diets included.

Is this accurate?

The periods and diets follow the mainstream scientific consensus. Palaeontology moves, so some details are revised over time - Spinosaurus in particular has been reinterpreted more than once.

Is the pick actually random?

Yes. Each dinosaur is drawn with your browser's cryptographic random source, so every one in the chosen group has an equal chance.