"At [40,000 pounds], I reckon it could have crushed a small car," Wroe told National Geographic News.
"Of course it would probably have broken most of its teeth in the exercise."
For comparison, T. rex, one of the largest land carnivores of all time, had a bite force that has been estimated at only 6,834 pounds (3,100 kilograms).
The work will be detailed in an upcoming issue of the Journal of Zoology.
Most of what is known about megalodon comes from the study of its teeth, which have features that suggest they were arranged in a broad mouth. And animals with broad mouths typically have short snouts.
Animals with short snouts, furthermore, generally have more leverage when they bite and generate more force in the up-and-down direction, scientists say.
Klimley, of the University of California, said megalodon's powerful bite is consistent with the theory that the ancient shark had a pug nose.
Chuck Ciampaglio, a paleontologist at Wright State University in Ohio, is more skeptical.
Megalodon was likely not a direct ancestor of great whites, Ciampaglio said, so it "may have quite a different skull and jaw structure."
Also, megalodon may have used fewer muscles to power its bite than the model predicts.
"As an animal becomes larger, much more of the animal's weight is consumed by support structures, not muscles," Ciampaglio said.
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