Is Godzilla Considered a Dinosaur?

Godzilla's enduring popularity is unmatched. While giant monster films were abundant in the 1950s, many, such as "The Giant Claw" or "The Beast From 20,000 Fathoms," faded into obscurity without sequels. Godzilla, however, thrived. The iconic kaiju first appeared on screen in 1954.

Over the years, Godzilla has featured in over 30 films across more than six decades. His latest appearance, "Godzilla vs. Kong," premiered in theaters and on HBO Max on March 31. While his origin story has been reimagined multiple times—often depicted as a prehistoric creature altered by radiation—the details differ in each film. One constant, though, is Godzilla's near-indestructible nature. But have you ever questioned how a creature of Godzilla's size could exist in reality? What exactly is Godzilla's biological classification?

Godzilla as a Dinosaur

Kenneth Carpenter, a former paleontologist and ex-director of Utah State University Eastern Prehistoric Museum, addressed this question in a 1998 essay for The Official Godzilla Compendium. Historically, Godzilla has been categorized as a theropod dinosaur, a group that includes all known carnivorous dinosaurs (such as T. rex) and birds.

Godzilla's skull, however, appears shorter and more rounded than typical theropods. Additionally, he is often portrayed with four fingers on each hand and features multiple rows of vertical, bony plates along his back and tail.

Based on these traits, Carpenter provisionally classified Godzilla within the ceratosauria, an early theropod subgroup. Similar to Godzilla, some ceratosaurians possessed osteoderms—bony deposits in the skin—on their backs. Species like the horned Carnotaurus sastrei also shared the characteristic of having shortened skulls.

Another distinguishing feature of ceratosaurians was their forelimbs. Carpenter explained via email that while some theropods had three, two, or even one-fingered hands, more primitive members like ceratosaurians typically had "four or more digits" per hand.

Maybe He's a Croc?

Does this mean Godzilla is definitively a ceratosaurian theropod? Not so fast, according to Victoria Arbour, Curator of Paleontology at the Royal British Columbia Museum. In a 2014 blog post, Arbour argued that Godzilla might not be a dinosaur at all. Instead, she suggested he could share more traits with crocodiles.

Crocodiles, alligators, and their ancient relatives belong to a reptilian group known as pseudosuchia. Arbour points out that features like osteoderms and four-fingered hands are more prevalent in pseudosuchians than in theropods. This raises the possibility that Godzilla might be better classified within this group.

Let’s take a closer look at Godzilla’s feet. In most of the classic Japanese films, Godzilla adopts a plantigrade stance, walking flat on his feet similar to humans. In contrast, digitigrade animals, like dogs, walk on their toes with their heels elevated.

"Modern crocodylomorphs are plantigrade, but it’s still unclear whether all pseudosuchians, especially bipedal ones, shared this trait," Arbour explained via email. Notably, no known dinosaur, including theropods, exhibited this flat-footed posture.

Do His Feet Hold the Answer?

In the 2014 American adaptation, Godzilla’s feet were significantly redesigned. "One could argue that the 2014 Godzilla has feet resembling those of a tortoise, with many tortoises being digitigrade, similar to elephants, featuring a large heel pad that supports upright toes," Arbour noted. She also highlighted that while "nearly all bipedal dinosaurs" had only three weight-bearing toes, this version of Godzilla maintains "at least four toes in contact with the ground."

Massive land animals, such as long-necked dinosaurs, typically have column-like, digitigrade feet, which are highly efficient at supporting enormous body weights. If Godzilla were a real creature, we’d likely expect him to have digitigrade hindlimbs, despite a 2017 study suggesting that plantigrade animals can deliver more powerful arm swings in combat—something Godzilla certainly loves.

However, it’s highly unlikely that Godzilla could realistically walk on land, regardless of his foot structure. "Having Godzilla stand upright and stationary would be impossible," paleontologist Donald Henderson explained in a 2019 email. "His bones couldn’t support his body weight, and his heart wouldn’t be able to pump blood to his head."

This issue stems from the square-cube law: As an object scales up, its mass increases much faster than its surface area. For example, doubling the height, width, and length of a wooden cube makes it eight times heavier than before.

Godzilla as a Marine Animal

How would Godzilla perform in an aquatic environment? Henderson, who works at Canada’s Royal Tyrell Museum and specializes in physics-related questions about prehistoric creatures, explored this in 2018. Using computer modeling, he tested whether Spinosaurus—a sail-backed theropod—was adapted for swimming. His findings revealed that the dinosaur’s deep body shape would have made it unstable and prone to tipping in water.

Would Godzilla’s osteoderms create similar instability? Henderson believes not. Based on his calculations, the back plates of Stegosaurus—a Jurassic herbivore that inspired Godzilla’s design—accounted for only 17 percent of its total body mass.

Godzilla’s plates, however, seem to make up an even smaller proportion of his overall mass. While Henderson would need to create a new digital model to confirm, he currently suspects that "Godzilla’s plates wouldn’t cause it to tip" while swimming.

Nevertheless, as a marine creature, Godzilla would encounter numerous challenges. Aquatic animals typically have streamlined bodies, but Godzilla’s jagged osteoderms and bulky legs are far from hydrodynamic. This would require him to expend significant energy to move efficiently through water.

"The most effective way for Godzilla to swim would be to undulate its body and tail, creating waves that propel it forward," Henderson explained. "Imagine how crocodiles and salamanders swim rapidly—they tuck their limbs close to their bodies and use lateral movements to push against the water, generating forward thrust."

Interestingly, semiaquatic behavior has been—and remains—common among pseudosuchians. In contrast, there’s no evidence that non-avian theropods were habitually amphibious. However, some did occasionally venture into water. In Utah, 190-million-year-old tracks reveal theropods paddling through shallow water, their toes barely touching the ground.

Carpenter, however, disputes the pseudosuchian classification. Given that theropods were capable swimmers, he argues that Godzilla’s aquatic tendencies don’t rule out his identity as a true dinosaur. Additionally, Godzilla shares numerous traits with ceratosaurians. If he isn’t part of this group, his ancestors likely developed these features independently—a process known as "convergent evolution." While possible, Carpenter believes the similarities between Godzilla and theropods are too extensive to be mere coincidence.

"Dr. Yamane, a character from the 1954 film, identified the original Godzilla as a dinosaur," Carpenter notes. "Since he was there firsthand, I’m inclined to trust his judgment."