Dino Size Comparator

Compare dinosaur sizes against each other and humans

Compare the sizes of any two dinosaurs side by side, with a human figure for scale. Visualize length, height, and estimated weight differences between species from tiny raptors to massive sauropods.

Mais comparações

Humano
1.8m

Selecione dois dinossauros acima para comparar seus tamanhos.

How to Use

  1. 1
    Select two dinosaurs

    Search for any two dinosaurs by name or browse by clade, period, or diet. The tool covers over 6,000 described species.

  2. 2
    View side-by-side scale

    A human silhouette at average height is rendered alongside both dinosaurs, giving an immediate sense of relative scale for length, hip height, and estimated mass.

  3. 3
    Explore the data panel

    Click either dinosaur to see the source formation, estimated body-mass range, and the scientific references behind the size estimates.

About

Dinosaur body size is one of the most studied topics in vertebrate palaeontology because it intersects biomechanics, ecology, physiology, and evolutionary theory. Body mass is rarely measured directly — it is inferred from bone circumference, particularly of the femur, using regression equations derived from living animals. The precision of any estimate therefore depends heavily on how complete the specimen is and how phylogenetically close the living comparators are.

The Mesozoic Era spans roughly 186 million years, from the Triassic onset around 252 million years ago to the end-Cretaceous mass extinction at 66 million years ago. Over that time dinosaurs diversified into every major terrestrial ecological role and achieved an extraordinary range of body sizes — from the sparrow-sized Microraptor to the multi-tonne titanosaur sauropods. Understanding that size range requires a consistent frame of reference, which is exactly what a human-scale comparator provides.

Modern size databases draw on the Paleobiology Database, individual formation monographs, and comparative anatomy studies published in journals such as PLOS ONE, PeerJ, and the Journal of Vertebrate Paleontology. Because new specimens are described every year, estimates for even well-known species are periodically revised. The DinoFYI size comparator reflects the most current published values and links each figure to its source so researchers and enthusiasts can trace the data provenance directly.

FAQ

How accurate are the dinosaur size estimates?
Size estimates for extinct animals are derived from scaling relationships between bone measurements and body mass established in living reptiles and birds. For well-represented species like Tyrannosaurus rex, multiple complete or near-complete specimens allow tight confidence intervals. For species known from fragmentary material, estimates can span a wide range. The tool displays both a median estimate and the documented uncertainty range so users can evaluate data quality themselves.
Why do different sources give different sizes for the same dinosaur?
Dinosaur size estimates are regularly revised as new specimens are found and as scaling methods improve. Historically, many estimates were based on isolated bones compared to related species. Modern methods use three-dimensional bone scanning and biomechanical modelling to generate more robust figures. The tool cites the most recently published peer-reviewed estimates and notes when a figure is disputed or based on limited material.
What is the largest dinosaur known from good fossil evidence?
Several titanosaur sauropods compete for the title. Patagotitan mayorum, described in 2017 from Argentina, is among the most completely known giants, with a reconstructed mass of roughly 69 tonnes based on femur circumference scaling. Argentinosaurus and a handful of other titanosaurs may have been larger, but their estimates rest on fewer bones. The comparator tool flags specimen completeness alongside each size figure.
Can I compare a carnivore against a herbivore?
Yes, the comparator has no restriction on which species can be paired. Comparing a large predator like Spinosaurus against a large herbivore like Diplodocus illustrates how body plan, not just length, determines ecological role. Spinosaurus was longer but had a much lighter, more elongated build suited to piscivory, while Diplodocus had a proportionally much heavier torso designed to house a large fermentation-based digestive system.
Does the tool show ontogenetic (juvenile) size stages?
For species where juvenile specimens have been formally described and measured, the tool offers an age-class selector so you can compare an adult against a juvenile of the same or a different species. Growth rate data, where published, is also shown. Dinosaurs grew at rates comparable to modern large birds and mammals, reaching adult size far faster than most reptiles.