Previously, I published a post about the largest crocodiles ever recorded. All sizes in that post were recorded in recent times. The crocs listed were large, yes, but not as big as most people think. But in the prehistoric ages, some animals were much bigger than today’s counterparts – including crocodiles. So, what was the biggest crocodile that ever lived on Earth? Here are the top six candidates – the top 8 biggest prehistoric crocodiles (actually, crocodilians) ever lived.

Before reading the post, keep in mind that the list given below can change at any time with any newly found fossil. Due to the absence of a complete enough skeleton in most cases, the numbers given are estimates.

A common method to estimate the size of crocodiles and crocodile-like reptiles is the use of the length of the skull measured in the midline from the tip of the snout to the back of the skull table since in living crocodilians there is a strong correlation between skull length and total body length in subadult and adult individuals.

Largest prehistoric crocodiles list

8. Sarcosuchus imperator (Up to 9.5 meters [31 feet])

Sarcosuchus
Sarcosuchus was one of the largest crocodiles that ever lived on Earth. Recent estimates suggest that the largest S. imperator specimen was 9.5 meters (31 feet) in length. They lived in the Early Cretaceous in the Sahara Desert some 110 million years ago before camels and Tusken Raiders became the dominant species. In the Cretaceous, the Sahara was once filled with waterways and lush jungles. Massive dinosaurs like Paralititan were hunted by predators like Carcharodontosaurus. In the water, however, Sarcosuchus would have reigned unchallenged. Its name means “Flesh Crocodile Emperor”. S. imperator probably had a generalized diet similar to that of the Nile crocodile. A diet that would have included large terrestrial prey such as the abundant dinosaurs that lived in the same region.

Sarcosuchus, popularly known as the “super croc” is an extinct genus of crocodyliform and a distant relative of the crocodile that lived 112 million years ago.

Most sources on the web claim that the Sarcosuchus imperator was the biggest prehistoric crocodile ever lived, but recent findings suggest that it was not the case. Recent estimates suggest that the largest S. imperator specimen was 9.5 meters (31 feet) in length and had a body weight of about 4.3 metric tons (4.7 short tons)

Fish are easy prey for small crocodiles but as they grew larger they would need more sustenance to survive and so they may have begun to incorporate dinosaurs into their diets as well.‭ ‬As seen in crocodiles today,‭ ‬Sarcosuchus may have also left the water to scavenge the kills of the larger dinosaurs as well.

Although it’s unlikely that Sarcosuchus deliberately hunted dinosaurs for lunch, there’s no reason it had to tolerate other predators that competed with it for limited resources. A full-grown SuperCroc would have been more than capable of breaking the neck of a large theropod, such as, say, the contemporary, fish-eating Spinosaurus, the biggest meat-eating dinosaur that ever lived.

Largest prehistoric crocodiles: Sarcosuchus imperator skeleton
Sarcosuchus imperator skeleton at Muséum National d’Histoire naturelle, Paris. Photo by Shadowgate from Novara, Italy – Museum of Natural History, CC BY 2.0, Link
Largest prehistoric crocodiles: Sarcosuchus vs human size comparison
Sarcosuchus imperator compared to a 1.8-meter-tall person

7 and 6. Euthecodon brumpti and Gryposuchus croizati (~10 meters / ~33 feet)

Euthecodon brumpti was a large slender-snouted fish-eating crocodile, that was common in the lakes and rivers of Lake Turkana (Kenya) between 1 and 8 million years ago, during the Neogene. A particularly large specimen of this crocodile found at Lothagam on the west side of Lake Turkana dated to some 4 million years, was estimated to (as explained above) have been almost 10 meters (~33 feet) in length.

Gryposuchus is an extinct genus of gavialoid crocodilian. It was also a slender-snouted crocodile-like Euthecodon. Fossils have been found in Argentina, Colombia, Venezuela, Brazil, and the Peruvian Amazon. The genus existed during the early and middle Miocene epoch. One recently described species, G. croizati, grew to an estimated length of 10 meters (33 feet).

Largest prehistoric crocodiles: Gryposuchus compared with a 1.8-meter tall person
Largest prehistoric crocodiles: A rough estimate of Gryposuchus compared with a 1.8-meter tall person.

5. Purussaurus (10.9 meters / 36 feet)

Purussaurus
Largest prehistoric crocodiles: Restoration of Purussaurus brasiliensis. Image by Nobu Tamura (https://spinops.blogspot.com) – Own work, CC BY 3.0, Link

Purussaurus was actually a caiman (see notes 1). It lived in South America during the Miocene epoch, 8 million years ago. It is known from skull material found in the Brazilian, Colombian and Peruvian Amazonia, and northern Venezuela.

Purussaurus is one of the largest known crocodyliforms ever to have existed. ‬Its body length is estimated at up to 10.9 meters (about 36 feet). But, as only its skulls have been found, its actual length is not certain. It was previously estimated at 12.5 meters (41 feet) but most scientists and experts are skeptical about these proportions.

The large size and estimated strength of this animal appear to have allowed it to include a wide range of prey in its diet, making it an apex predator in its ecosystem. As an adult, it would have preyed upon large to very large vertebrates with no real competition from sympatric, smaller, carnivores.

Largest prehistoric crocodiles: Purussaurus vs human size comparison
Largest prehistoric crocodiles: A rough estimate of Purussaurus compared with a 1.8-meter-tall person.

4. Rhamphosuchus (up to 11 meters / 36 feet)

Largest prehistoric crocodiles: Rhamphosuchus
Largest prehistoric crocodiles: Rhamphosuchus

Previously, it was believed that the Rhamphosuchus was the largest prehistoric crocodile ever, but not anymore: for many years scientists believed that it was one of the largest, if not the largest crocodylian that ever lived, reaching an estimated length of 15 to 18 meters (49 to 59 feet) and 20 tons in weight. However, a more recent study suggests that the animal may have been 8-11 meters (26-36 feet) in length, and therefore is not the largest known crocodylian.

Rhamphosuchus inhabited what is now the Indian sub-continent in the Miocene. It is only known from incomplete sets of fossils, mostly teeth, and skulls.

Largest prehistoric crocodiles: Rhamphosuchus vs human size comparison
Largest prehistoric crocodiles: A rough estimate of Rhamphosuchus compared with a 1.8-meter-tall person. Rhamphosuchus reconstruction s based upon the proportions of a false gharial.

3. Mourasuchus (up to 12 meters / 39 feet 4 in)

One of the largest prehistoric crocodiles, Mourasuchus is an extinct genus of giant crocodilians from the Miocene of South America. With an estimated length of up to twelve meters long,‭ ‬Mourasuchus was one of the biggest crocodiles of all time.

‭‬However, despite this gigantic size, it had a relatively weak jaw and skull construction combined with quite small teeth for its size: the skull has been described as duck-like, broad, flat, and very elongated.

‬These two things do not portray an apex predator that wrestled large prey into the water. It presumably obtained its food by filter-feeding; the jaws were too gracile for the animal to have captured larger prey. It also probed the bottoms of lakes and rivers for food.

Fossils have been found in the Fitzcarrald Arch of Peru, where it coexisted with many other crocodilians, including the giant gharial, Gryposuchus, and the alligatorid Purussaurus. The great diversity of crocodylomorphs in this Miocene-age (Tortonian stage, 8 million years ago).

Largest prehistoric crocodiles: Mourasuchus-human size comparison
Largest prehistoric crocodiles: The upper estimate of Mourasuchus compared with a 1.8-meter tall person. Photo: prehistoric-wildlife.com

2. Deinosuchus (up to 12 meters / 39 feet 4 in)

Largest prehistoric crocodiles: Deinosuchus hatcheri skeleton
Largest prehistoric crocodiles: A reconstructed Deinosuchus hatcheri skeleton at the Natural History Museum of Utah. Photo: Wikipedia

Deinosuchus is an extinct genus related to the alligator that lived 80 to 73 million years ago (Ma), during the late Cretaceous period. The name translates as “terrible crocodile” and is derived from the Greek deinos, “terrible”, and soukhos, “crocodile”. The first remains were discovered in North Carolina (United States) in the 1850s; the genus was named and described in 1909.

Deinosuchus was far larger than any modern crocodile or alligator, with the largest adults may have been up to 12 meters (39 feet) in length and perhaps weighing as much as 8.5 metric tons (9.4 short tons).

Deinosuchus’ overall appearance was fairly similar to its smaller relatives (today’s alligators).

Deinosuchus was an apex predator and probably capable of killing and eating large dinosaurs. It may have also fed on sea turtles, fish, and other aquatic and terrestrial prey.

The incredibly strong bite force of Deinosuchus has been estimated to be 18,000 N (1,835 kgf or 4,047 lbf) to 102,803 N (10,483 kgf or 23,111 lbf), which makes its bite force even stronger than that of Tyrannosaurus rex (which is estimated at about 35,000 N. For comparison, today’s largest and strongest crocodile, the saltwater crocodile has a bite force of about 16,000 N.

Deinosuchus was almost the same length as Mourasuchus, but was heavier, and had much more bite force.

Largest prehistoric crocodiles: Deinosuchus attacks a T-rex
Largest prehistoric crocodiles: Deinosuchus was an apex predator and probably capable of killing and eating large dinosaurs. Image: Deinosuchus attacks a T-rex on Deposit Photos
Two deinosuchus attack on dinosaurs
Deinosuchus was far larger than any modern crocodile or alligator, with the largest adults measuring up to 12 meters (39 feet) in total length, its overall appearance was fairly similar to its smaller relatives (today’s alligators).

1. Aegisuchus (up to 15 meters/49 feet). The largest crocodile ever lived on Earth

Aegisuchus lived during the Late Cretaceous (100.5-66 million years ago). It is only known from a partial braincase, but even that part gives hints about its enormous size: its braincase is much larger in volume than that of any other crocodyliform (about 40 cm3 or 2.44 cubic inches). Based on this volume, we can compare the ratio of braincase to skull length in other crocodilians: the total skull length of Aegisuchus is estimated to have been 2.08 to 2.86 meters (6.8 to 9.4 feet) in length. So:

  • If it had a long long snout like modern-day gharials, its total body length (from snout to tail) should be 15 to 21 meters (49 to 69 feet).
  • If it had a short snout like today’s crocodiles its length should be a whopping 16 to 22 meters (52 to 72 feet)!

But, most scientists think that these calculations gave an (almost) impossible length for this prehistoric crocodilian. They think Aegisuchus was 15 meters (49 feet) in length at most. Still, this makes Aegisuchus the largest crocodile ever lived on Earth.

Notes

  1. A Caiman is an alligatorid crocodilian belonging to the subfamily Caimaninae, one of two primary lineages within Alligatoridae, the other being alligators. Caimans inhabit Central and South America. They are relatively small crocodilians.

Sources

M. Özgür Nevres
Latest posts by M. Özgür Nevres (see all)

Join the Conversation

18 Comments

    1. Their body types were similar, but I think it is Rhamphosuchus. The source of the photo was also saying so.

  1. this article was very helpful. Thank you for writing and posting it! it helped settle a dispute among 3rd grade students in Osceola Mills, PA.

  2. Can’t compete with Tyrannosaurus Rex’s bite force!?!?!?!
    T. Rex had a maximum bite force of 57,000N.
    That’s nowhere near the pressure of 88,000N!

    Furthermore…. where was the mighty Machimosaurus Rex???
    Machimosaurus is said to be as large if not larger than Sarcosuchus Imperator.
    Also, what about Sarcosuchus Hartii???
    Either this is an old article and you’ve done well to cover yourself or you didn’t look into your studies enough.

    1. Hi, Rhys
      Thanks for the comment!

      You’re right, the estimated bite force of T-Rex is about 57,000N. One study for 2003 puts it as high as 183,000 to 235,000 Newtons but I think it’s an exaggeration. So I fixed the article.

      Yes, it is a bit an old article, but I don’t think the Machimosaurus Rex was bigger than Sarcosuchus. It is 30 feet long, shorter than Sarcosuchus.
      I couldn’t find the size information of Sarcosuchus hartti, can you provide a source, please?

      Many thanks

  3. Nice, but the lowest estimate for Purussaurus is actually 10.3 m. Also, now we have a lower estimate for Sarcosuchus at 9-9.5 m as well.

  4. Sarcosuchus is not the largest, Aegisuchus was even bigger. While most Ageisuchus only reach 26~ feet, there are some that reached a mind blowing 72 feet long.

Leave a comment

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.