It can be difficult to clock the speeds of animals that lived over 66 million years ago. There’s no speedometer to know how fast they could run or even any muscular soft tissue to fully understand the anatomy of the most speedy predators. Still, paleontologists do have some ideas about how fast our favorite dinosaur predators could run.

The only direct evidence we have of dinosaur locomotion comes from trackways or the fossilized footprints of dinosaurs, says Scott Persons, an assistant professor of paleontology at the College of Charleston. From a well-preserved dinosaur footprint, you can get the dimensions of its foot, and from that, you can estimate the length of its leg and discern its stride length.

“This, combined with a lot of careful work done on modern-day animals and their running biomechanics, provides a pretty good estimation for how fast a dinosaur was when it was leaving those footprints,” says Persons.

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Still, dinosaur trackways don’t tell the whole story because most of these dinosaurs were just “plodding along,” and they weren’t in any hurry. That’s because trackways were often made in the mud, and as we know from walking in the mud, it’s not a time to run. Not to mention that when a dinosaur was walking slowly, the track would have been deeper and more likely to preserve. 

Some would say the most popular dinosaur predator of all time is the Tyrannosaurus rex. Starting around 83 million years ago, this mega-predator would have ruled its environs, noshing on everything from Triceratops to Ankylosaurus to Edmontosaurus and everything in between. It was big, with teeth the size of bananas and a powerful bite force. But what’s less well known is how T. rex chased after its prey.

There’s long been a debate amongst paleontologists about whether T. rex could even run. At 40 feet long and upwards of 11,000 pounds, jogging seemed difficult. But, according to Persons, a huge predator like T. rex could likely bring things up to a meaningful pace at around 25 mph. It’s also likely that T. rex's smaller Tyrannosaur cousins, Gorgosaurus, a type of tyrannosaurid, would have been even faster and among the fastest of all the dinosaur predators, says Persons.

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When you’re discussing whether a dinosaur was fast or not, it’s important to define whether you’re talking about sprint speed or endurance. The same is true of survival today. While cheetah clocks in 65 mph for short bursts of speed, pronghorns can reach speeds of up to 60 mph, but for longer periods of time. 

Take the Troodon for example. As one of the smartest dinosaurs, it had the largest brain-to-body ratio of any of the other dinosaurs. And we also know that this small theropod could likely run fast, though we don’t know how fast. 

Troodons had long shin bones and long metatarsals, or the bones that are in the flats of the foot, says Persons. We know from other modern animals like cheetahs that long leg bones below the knee are important for fast speeds. Velociraptors, on the other hand, couldn’t have run as fast as Troodons because they didn’t have the same leg bone structure.

It was also the case that prey of the Age of Dinosaurs likely had endurance. Judging by their leg bones, Persons says that Hadrosaurs, or duck-billed herbivore dinosaurs, could likely keep running for longer periods of time to escape predators. 

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Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:

• Scott Persons, an assistant professor of paleontology at the College of Charleston

• Natural History Museum. Tyrannosaurus

• University of Tasmania. Is the cheetah the fastest animal in the world?

Sara Novak is a science journalist based in South Carolina. In addition to writing for Discover, her work appears in Scientific American, Popular Science, New Scientist, Sierra Magazine, Astronomy Magazine, and many more. She graduated with a bachelor’s degree in Journalism from the Grady School of Journalism at the University of Georgia. She's also a candidate for a master’s degree in science writing from Johns Hopkins University, (expected graduation 2023).