Giganotosaurus vs. T Rex: Who Was The Deadliest Predator?

The Tyrannosaurus Rex is without a doubt one of the coolest dinosaurs that ever lived. With its enormous size, speed, and killer (literally) jaw power, it’s hard to deny that it was ferocious, fierce and beautiful. Well, at least as long as beauty is measured in the strength to rip apart those around you. Anyway, the T-rex has definitely gotten its fair share of attention. From starring in the Jurassic Park movies and being the most talked about dinosaur to becoming everyone’s entertainment when their Internet isn’t working, the T-Rex is part of our common culture. 

Unfortunately, the absolute superiority of the T-rex must now be questioned. The Giganotosaurus, a massive dinosaur that existed 30 million years before the T-rex, seems to be a respectable rival. I’d hate to take the crown from the king of the dinosaurs and simply hand it to the Giganotosaurus though, so here’s an analysis to see who was the more capable predator.


Contrary to popular belief, the T-rex is not the largest dinosaur in history. The Giganotosaurus wins this round. With a weight that may have been up to 14 tons (Around 8000kg) for the bigger ones, and a length between 40 and 43 feet, they defeat Sue (the largest and most complete specimen of a T-rex), who weighed about 9 tons with a length of around 40 feet.

We’ve found only two specimens of Giganotosaurus, so this also gives them the benefit of doubt that there may be even bigger ones out there.


The size of a Giganotosaurus as compared to a human being. (Photo Credits: Durbed/ Wikimedia Commons)

Giganotosaurus 1 – T Rex 0


While speed may not be the most important thing for dinosaurs as large as these, when it comes to being a great predator, it’s still definitely something you have to consider.

The speed of a dinosaur is estimated by reconstructing a dinosaur’s muscle structure, density, using the length of limbs, estimated center of mass, etc. The comparison of the distance between two consecutive footprints (in a sequence of preserved footprints) and the size of each footprint is another method used to estimate the movement speeds of ancient dinosaurs. However, these methods are very complicated and there are many difficulties that scientists encounter when trying to estimate the speed of a dinosaur.

The top speed of a T-rex has been a controversy for many years now. While some scientists estimate the top speed to be 16km/hr (10mph), there have been other estimates at 72.4km/hr (45mph) too. The Giganotosaurus, on the other hand, is assumed to have been able to run at a speed of 50km/hr (31.3mph).

However, given the inconsistency of the subject, and since there is no obvious winner, we must call this round a tie.

Giganotosaurus 1 – T Rex 0

Body Shape and Structure

Both of these dinosaurs had a long body, large legs, a huge skull and two very tiny arms. The T-rex had two fingers at the end of each forearm, while the Giganotosaurus had three. Not much is known about the functions of these arms.

Both of these dinosaurs had strong, muscular thighs, which benefited their running abilities. Both dinosaurs also had long, thick tails that helped balance the weight of their skulls (which were very big and heavy). However, it seems that the T-rex had a heavier tail than that of the Giganotosaurus. The Giganotosaurus had a more lean, pointed tail, which probably contributed to its agility and ability to make quick, sharp turns.

size comparison of dinosaurs

Comparison between the size of a T-rex (Black) and Giganotosaurus (Green) (Photo Credits: Dinoguy2/ Wikimedia Commons)

The anatomy of the Giganotosaurus seems to have made it a better predator.

Giganotosaurus 2 – T Rex 0

Jaw Power

While the speed and anatomy of the two dinosaurs seem somewhat comparable, the jaw power of the T-rex was probably a lot greater. It was capable of biting with a force of 35586 N (8000 pounds of force), which is a force similar to the weight of three small cars, or two medium-sized ones!

The not-so-immense jaw power of the Giganotosaurus, on the other hand, kept it from eating other dinosaurs whole, which it could have easily done otherwise, given the size of its mouth.

Giganotosaurus 2 – T Rex 1

Dental Structure

Another important factor for predators is the structure of their teeth. While the Giganotosaurus had almost all identical teeth, which were flat and wide, like blades, the T-rex had a set of teeth with a few different types. The front teeth were meant for gripping and pulling, the side teeth were meant for tearing the flesh and the back teeth were used for chewing the flesh. In a very basic way, that’s actually a lot like the structure of our teeth. We use incisors to bite into our food, canines to tear through it and back molars to chew it. Of course, they ate other dinosaurs, and while we eat dinosaurs too…. it’s not really the same…

dinosaur nuggets

Dinosaur nuggets like these are about the size of your finger. The dinosaurs which the T-rex ate on the other hand, were bigger than two of you put together! (Photo Credits: Dirk Ingo Franke/ Wikimedia Commons)

Basically, the T-rex seems to have had a far more developed dental structure than that of the Giganotosaurus, which seems about right, seeing as it had an extra 30 million years to evolve.

T-rex teeth

The teeth of a T-rex (Photo Credits: Imgflip)

Giganotosaurus 2 – T Rex 2


As mentioned earlier, both of these dinosaurs had huge skulls. The Giganotosaurus had a skull measured at 5.2 feet (1.6m), while the T-rex had a skull measured at about 5 feet (1.5m). Although the skull of the Giganotosaurus was bigger, the Giganotosaurus’ brain was smaller and shaped like a banana. The T-rex’s brain was larger and wider. A recent study also found that ancestors of the T-rex developed advanced brain functions and sensory perceptions long before they grew to their maximum size, which is likely what led to some of their very evolved features in the first place. In fact, the T-rex was actually one of the smartest dinosaurs.

Giganotosaurus 2 – T Rex 3

Therefore, the winner is the Tyrannosaurus Rex!

While these factors of eligibility are purely based on my opinion, the T-rex does retain the title as King of the Dinosaurs. However, the Giganotosaurus sure put up a great fight.

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If it wasn’t for that one god-forsaken meteor, dinosaurs would probably still be here. You, me and the rest of the 7.2 billion humans on Earth wouldn’t, but the world would still be a cooler place.

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Team ScienceABC is the handle of a team of engineers and science graduates who come up with brilliant ideas every now and then, but are too lazy to sit at one spot to complete an article, and dread the idea of being considered ‘regular writers’.

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