Domestic cat vs human bite force

by Michael Broad · April 9, 2021

Humans bite harder than domestic cats. There are a few ways to measure bite force, two of which are: psi (pounds per square inch) and bite for quotient (BFQ). The latter makes comparisons more accurate because it takes into account the size of the animal. But I can’t find a comparison of BFQ for humans versus cats and the formula for BFQ is complicated. Other measures of bite force are newtons and lbf (pounds force). It is certainly confusing and irritating.

Bite force humans versus domestic cats. Image: MikeB from images available in the public domain.

On a straight psi comparison it is said that cats are at 20-75 psi while humans bite at between 150-160 psi (Pamela Wissenbach on Quora.com). The human has a pretty strong bite as does the domestic cat. Considerable jaw power is needed to hold and kill prey. They have a sagittal crest to which the main chewing muscles are attached. Humans have a stronger bite (1100-1300 Newtons) than orangutans (National Geographic).

However, unlike humans, it is difficult to measure bite force in dogs and cats because chewing action cannot be directed – Frontiers in Veterinary Science.

The bite force comparison is muddied up by two factors: as mentioned, our relative sizes (bigger animals should bite harder) and the type of tooth concerned. The sharper the tooth the higher the bite force at the tip. Humans have flat molars while cats have scissor-like carnassial teeth to cut flesh. Out molars grind the food.

So it is complicated. Dogs bite at between 200 and 450 psi. The highest psi bite force in a living animal was a crocodile at 3,700 psi! Gorillas are at 1,300 psi.

Of all the cats, wild and domestic, the jaguar has the strongest bite (1,500 psi) which is why they have developed a simple but effective way of killing some prey animals: stick their canine teeth through the skull! Normally the big cats bite the neck of large prey to suffocate. Jaguars consider turtles to be prey and they bite open the carapace.

Taking the BFQ as a measure the domestic cat’s is 67 while the domestic dog’s is 114. The diminutive sand cat – a desert dwelling wild cat – has a BFQ of 130 compared to the jaguar’s at 137. The tiger is 121, lion 112 and leopard 94.

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