This is probably the question that all Paleontologists get asked at some point. Who would win in a fight between Tyrannosaurus Rex and Spinosaurus.

T. rex and Spinosaurus were among the two most ferocious predators ever to live on the planet. Both were the undisputed kings of the world’s they lived in, but both lived many millions of years and several continents apart from each other.

Still in this article I will be taking a look at all of the monsters strengths and weaknesses to try and decide who would win in a death match between these two kings of the Dinosaur world.

This article will try and look at things in a fair and balanced way. I freely admit I am more of a T. rex fan than a Spinosaurus fan, but this will be looking at cold hard facts.

The Tyrant

VS

The Pharoh

First up lets take a look at both beasts.

Tyrannosaurus Rex is by far and away the most famous Dinosaur. It was also among the last Dinosaurs to have ever existed, living at the tail end of the Cretaceous period 66 million years ago.

For over 90 years Tyrannosaurus was believed to be the largest land based predator of all time, but we now know that there were three larger meat eating Dinosaurs. Giganotosaurus, Carcharodontosaurus, and finally Spinosaurus itself now thought to be the largest.

Still Tyrannosaurus Rex was the largest predator in its environment. It was over 40 feet long, 18 feet tall at the hips and could weigh anywhere between 9 long tons and 21 short tons. Tyrannosaurus would have preyed upon Hadrosaurs, Ceratopsians and sauropods such as Edmontosaurus, Triceratops and Alamosaurus.

Whilst T. rex may no longer be considered the largest land based predator, in terms of raw power it is still utterly unrivalled. For instance. Tyrannosaurus is believed to have had the strongest bite force of possibly any animal ever to live on the planet.

In 2005 the BBC documentary the Truth About Killer Dinosaurs built a reconstruction of a T. rex head called Steely Dan.  Steely Dan revealed a number of interesting things about the power of a Tyrannosaurus.

First of all its bite was believed to have been a little over 4 tons. This would have given T- Rex a stronger bite than any animal alive today and a stronger bite than any other meat eating dinosaur (including Spinosaurus). With a bite of 4 tons Tyrannosaurus could have easily crushed a small car in its mouth no problem. It also would have been able to rip off more than 500 pounds of flesh in one bite.

T. rex could fit a whole lion in its mouth easy!

Furthermore due to having such a powerful bite. Tyrannosaurus Rex’s entire skeleton would have been stronger than reinforced steel and that’s just its skeleton. Think of how powerful the animal overall would have been when you add the muscles and thick skin over that!

Whilst this documentary was ground breaking at the time in the ten plus years since further studies have been conducted. In 2009 a study by Gregory Erickson suggested that Tyrannosaurus Rex would have had a bite force of over 9 tons. Over twice that of Steely Dan’s!

Other studies by Gregory M Erikson in 2012 have placed the Tyrannosaurs bite at over 6 tons instead and this is generally the most accepted estimate. Finally an earlier study by Mason B Meers stated that Tyrannosaurus could have had a bite force exceeding 23 tons.

If this estimate were true then it would mean Tyrannosaurus would have had the strongest bite force of any animal ever to live on the earth.

The Megalodon shark has a bite force of just over 20 tons. Deinosuchus a prehistoric crocodile had a bite force of just over 11 tons. Spinosaurus’s bite force was over three tons. A Great White Shark’s is 1 ton, and a Tiger which has the largest bite of any land mammalian carnivore has a bite force of just over half a ton.

T. rex therefore based on Meers estimated, could bite over twice as hard as Deinosuchus, 8 times as hard as Spinosaurus and close to 50 times as hard as a tiger.

As if that wasn’t enough Tyrannosaurus’ teeth were also designed with little meat hooks on the inside of every tooth that would pull more and more meat from its victims into its throat, the more they tried to struggle free.

T. rex’s were also incredibly durable animals overall, with Tyrannosaurus skeletons having been shown to have healed from gruesome injuries that would have killed other animals such as a broken neck, bite marks from other Tyrannosaurus in the brain case, scratches from Triceratops horns. Even whacks from Anklyosaur clubs (which could swing with a force of over 4 tons.)

Finally as if that wasn’t enough Tyrannosaurus Rex also was a highly intelligent animal, at least by Dinosaur standards. It was in fact believed to be the most intelligent giant Dinosaur. At the very least it was most likely smarter than Alligators and Crocodiles, who are in turn more intelligent than some species of cats and dogs. If you were brave enough you could even teach a T. rex tricks!

Some experts believe that Tyrannosaurus Rex’s intelligence may very well have been greater than that of a Lion’s however.

A T. rex couldn’t have hugged you as its arms were too small, but it could have loved you just as much.

T. rex’s larger brain would also have allowed its senses to be much more refined and advanced too. Its sense of vision was particularly strong and its sense of smell was according to Bob Bakker one of the worlds leading experts on Dinosaurs, comparable to 100 blood hounds.

https://www.sciencefocus.com/nature/inside-the-mind-of-a-dinosaur-2/#:~:text=In%20fact%2C%20not%20only%20was,could%20hear%20low%2Dfrequency%20sounds.

Spinosaurus meanwhile was a relatively obscure Dinosaur for decades until it shot to fame when it starred in Jurassic Park 3 in 2001.

Spinosaurus was the largest land based predator ever to live on the planet. This was not conformed until 2006 however. Spinosaurus could reach a length of 59 feet long and weigh anywhere between 7 and 23 tons. It was also roughly about 20 feet tall at the hips. Spinosaurus lived during the early to middle Cretaceous period 112 to 93 million years ago.

It was the apex predator in its environment, though there is some evidence that it came into conflict with another giant meat eating dinosaur named Carcharodontosaurus which was larger than T. rex. One Spinosaurus specimen possessed the bite mark of a Carcharodontosaurus on its sail.

Spinosaurus would have preyed on other large Dinosaurs, but there is evidence that its diet consisted of mostly marine life. It was a semi aquatic animal that spent a good deal of its time in the water. Don’t think this makes it any less impressive a hunter however. The marine life it preyed on would have included massive predators far larger and stronger than the Great White Shark or the Giant Squid!

Spinosaurus’s teeth were better designed for gripping long slippery prey which is why they were thinner than the robust teeth of Tyrannosaurus Rex. Spinosaurus also had a considerably smaller bite than Tyrannosaurus at just 3 tons. Though that is still far greater than any animal alive today and would have been powerful enough to bite through a car door, or bite a human being in half. Its still quite small for an animal of that size however. Spinosaurus was also not as intelligent as Tyrannosaurus or as fast.

Where it did have an advantage over Tyrannosaurus however aside from its greater size was in the huge claws on its arms.

Now we all know about Tyrannosaurus Rex’s little arms. They’ve been the punch line of many jokes and meme’s over the years. In reality those little arms were still surprisingly strong, and as we have seen Tyrannosaurus really wouldn’t have needed them due to its powerful bite.

Still just as T. rex didn’t need big arms Spinosaurus, it can be argued didn’t need a colossal bite either.

The claws on its fingers were as massive as the meat hooks you’d find in a slaughter house and could have very easily pierced the hide of a Tyrannosaurus Rex no problem. (We know they could at least be useful weapon in fighting off a Charcharodontosaurus, which is of a similar size to a Tyrannosaurus.)

With this in mind both animals are at least clearly capable of killing the other, but in terms of who would be more likely to get that chance? There are many factors to take into consideration.

Chief among them is the environment. If the two beasts are out in the wild well then it really could go either way, as there are so many things that could tip it in the other animals favour out in the wild. To start with one of the animals may be sick or old, or one may be alone going against a family unit, one may be fighting to kill, whilst the other is simply fighting to defend its territory. Also it depends on where they are fighting.

If its in the jungle Tyrannosaurus is going to have the advantage. Not only will it be more familiar with the environment, but it will also be more manoeuvrable too. It’s also faster on the land and it’s not hindered by that big sail. Down by the water however Spino obviously has the clear advantage. In the water it is now faster, it can strike like lightening, and it could easily leap out and grab a Tyrannosaurus and pull it into the water.

Trying to say who would win in a fight between Tyrannosaurus and Spinosaurus in the wild is like saying who would win in a fight between a Crocodile and a Lion.

Sometimes the Croc will win, sometimes the Lion will kill the Croc for various reasons. You can never say who will win for sure based solely on speed and bite force, both of which are mismatched in the case of a Croc vs Lion.

If Tyrannosaurus and Spinosaurus did get brought back from extinction, either through cloning or time travel and were forced to live on the same island. They most likely would never bother each other. Large carnivores like Crocodiles and Lions generally give each other a wide berth.

A fight with another large predator could end very badly even for the victor. A Lion might kill a Crocodile, but the Croc could still break its leg in the fight preventing the Lion from being able to hunt, fight off other Lions or defend its territory.

Unless they are desperate, most large predators will instead hunt herbivore’s who aren’t as big a threat to them and Tyrannosaurus and Spinosaurus would most likely be the same.

I’d give Tyrannosaurus and Spinosaurus a 50/50 chance of killing each other in the wild due to the fact that both can kill each other, and the many outside factors that would have to be taken into consideration.

What about in more controlled circumstances however?

Lets imagine its an alternate universe where the Dinosaurs were never driven to extinction and small intelligent meat eating Dinosaurs evolved into intelligent humanoids, Dinosauroids.

Believe it or not Richard Dawkins has said that this could have happened.

The Dinosauroids develop an advanced society and just as we used to capture Lions and Tigers and pit them against each other in death matches to see who was the king of the Jungle. Lets imagine the Dinosauroids start capturing Spinosaurus and Tyrannosaurus and pit them against each other in order to see who is the king of the beasts.

This is a fair fight. Two young, healthy males, in an arena that is a completely neutral environment. No jungle, no water. Both are land animals (even if Spinosaurus spent a lot of time in the water.) Both are hungry and have no way of escape. Who wins this fight?

Well once again we have to take certain factors into account.

How big are the Tyrannosaurus and the Spinosaurus for instance?

If its a twenty three ton Spinosaurus against a 9 ton Tyrannosaurus then forget it. It’s a curb stomp in favour of Spinosaurus. The size difference between the animals in that scenario is too big. Yes a 9 ton Tyrannosaurus would still have a bigger bite than a Spinosaurus, but sadly that wouldn’t do it any good.

Plenty of predators with massive bites are still killed by predators larger than they are.

Take a look at Lions vs Hyena’s or Killer Whales vs Great White Sharks. The White Shark and the Hyena have bigger bites than the Lion and the Killer Whale, but they still always lose in one on one fights because the other predator is just too big to mess with.

The size difference between a 23 ton Spinosaurus and a 9 ton Tyrannosaurus is not quite the same as that between a Shark and a Whale, but the Spino is still close to 3 times heavier than the Rex.

Still this is not exactly a fair fight. Taking the highest estimate for Spinosaurus and pitting it against the lowest for Tyrannosaurus. Remember that Tyrannosaurus was said to have reached possibly 21 short tons in which case there is only a two ton difference between them.

Also remember that whilst most experts agree that Spinosaurus was longer than Tyrannosaurus, many believe that it was not as heavy as it had a considerably lighter build and frame.

So with this in mind if we did have a Tyrannosaurus that was heaver even just by a ton against a Spinosaurus. I think it would be a curb stomp in favour of the Tyrannosaurus. Spino’s biggest advantage is its superior weight, and without that then Tyrannosaurus is its superior in every way. Faster, smarter, stronger. Spino is sadly outclassed and an angry bull Rex could rip it limb from limb. The same applies for two specimens the same size.

In order for this to be a fair fight for both lets have a 21 ton Tyrannosaurus go up against a 23 ton Spinosaurus or a 7 ton Tyrannosaurus go up against 9 ton Spinosaurus.

Lets also say that this is a two legged Spinosaurus. Some experts believe that Spinosaurus was a four legged animal, though there is not conclusive evidence for this. A four legged Spinosaurus would be at a real height disadvantage against a Tyrannosaurus. Its neck would be right open to a more fleet footed in comparison Tyrannosaurus. Whilst the Spino could still perhaps rear up to use its claws, overall it would be too awkward to use them against a Tyrannosaurus. Those who believe Spinosaurus was a four legged animal believe that on land the creature would have been clumsy as its legs were small. Really I think this would be another fight that would be overwhelmingly in favour of Tyrannosaurus.

So lets make this fight between a two legged 59 foot long Spinosaurus that weighs 23 tons and a 42 foot long Tyrannosaurus that weighs about 21 tons.

Who wins this fight?

Well again I’d give this to Tyrannosaurus Rex. It wouldn’t be a curb stomp. I’d say Tyrannosaurus would win 60 percent of the time.

Fact is as ferocious as Spinosaurus is, it’s simply outclassed in too many ways by old Rexy.

To start with T. rex is faster which is very important in a fight. Also T. rex is smarter. Now you might not think that matters with two animals but it does. For instance in fights between Lions and Tigers, the Tigers greater intelligence is a huge advantage as the Tiger is smart enough to rear on its back legs, unlike the Lion who only strikes with one paw. The Tiger can strike the Lion in the face with both paws and overwhelm it. Likewise killer whales when fighting Great Whites will often flip them on their belly and hold the Shark upside down until it passes out.

Whose to say in a similar confrontation, Tyrannosaurus wouldn’t be able to figure out any weaknesses Spinosaurus had? It certainly would be more likely to than Spinosaurus.

Also in terms of weapons Tyrannosaurus has the advantage. To start with its jaws are much more deadly than Spinosaurus claws and it can use them a lot more easily.

When the two animals faced one another Tyrannosaurus could reach out and bite Spinosaurus on the neck much more easily than Spino could use its claws.

When the two predators faced the weapons they would both be more likely to use would be their jaws. Spinosaurus’s arms would have been too short to reach out and grab the Tyrannosaurus. It’s not like King Kong, whose arms can reach out and hold the Tyrannosaur at bay before it can bite him.

See how Kongs arms are useful weapons because they are long. Spino’s though bigger than Tyrannosaurus’s could not reach out past its face.

If Tyrannosaurus and Spinosaurus faced each other then they would rely on their jaws, as in order to use its claws then Spinosaurus would have to get too near to Tyrannosaurus and leave itself open to a bite.

In a biting match it’s obvious who’s going to win. Tyrannosaurus Rex’s were known to bite each other in the face regularly and since their bites were possibly almost 8 times that of a Spinosaurus, then its safe to say T. rex could take a bite from a Spinosaurus to the face. Spinosaurus meanwhile would most certainly not be able to take a bite from a Tyrannosaurus.

All Tyrannosaurus would need would be one bite and the Spinosaurus would be finished. If it bit it on the neck it would crush the bones in its neck effortlessly. Even the lowest estimates of a Tyrannosaurus bite which are now thought to be inaccurate could crush an entire car and rip off over 500 pounds of flesh. A Spinosaurus’ neck would be no problem whatsoever.

Even if Tyrannosaurus bit Spinosaurus on the arm it would have been strong enough to rip the animals entire arm off. Even if it just bit Spinosaurus on the side then it would have ripped off 500 pounds of flesh and crush whatever bones it bit into.

The fact that Tyrannosaurus Rex was faster and had better vision would have given it a much better chance of striking a deadly blow against the Spinosaurus too.

Spinosaurus’s claws though deadly weapons could not have killed Tyrannosaurus instantly. I think it would need a few slashes to bring it down. Remember Tyrannosaurus’s are animals that could withstand injuries like a bite to the brain case or a broken neck. It would take a while for Spinosaurus’s claws, which would be very difficult for it to use anyway.

Spinosaurus also could not use its claws to twist Tyrannosaurus’s neck like in Jurassic Park 3 as Spinosaurus’s hands could only face each other as though they were clapping. If they tried to bend round and face down then they would have broken. The same is also true of all other meat eating dinosaurs including Tyrannosaurus itself.

All Spinosaurus could use its claws for therefore, would be to slash Tyrannosaurus from side to side across the face.

I could see Spinosaurus kill Tyrannosaurus two different ways in this scenario. It could quickly ram Tyrannosaurus and knock the monster off its feet which its superior weight would allow it to do. When Tyrannosaurus was on the floor it would be easier for Spinosaurus to slash at Tyrannosaurus with its claws. Provided it went for the Rex’s throat it could get a quick kill if it cut its jugular.

Another scenario where Spinosaurus could win against the Rex would be if it bit it on the neck and pulled the T. rex towards its arms which its superior body mass might allow it to do. It would then uses its claws to repeatedly slash at Tyrannosaurus’ face and its eyes over and over again until the pain and blood loss weakened Tyrannosaurus to the point where it couldn’t fight back.

Whilst it most certainly would be possible for the Spinosaurus to kill the Tyrannosaurus these ways, at the same time Spinosaurus would be putting itself in danger. When Tyrannosaurus fell on the ground and Spinosaurus tried to slash it Tyrannosaurus could reach up and bite its arm, crushing it. Or similarly when Spinosaurus got Tyrannosaurus by the neck, T. rex could reach up and bite the Spino on the neck in which case once again it would be over for the Spinosaurus, or the Rex could bite at its arms too.

Tyrannosaurus on the other hand I can see winning more easily. The two would face each other and charge at each other instinctively using their jaws, Tyrannosaurus who is a lot faster would be able to dodge its opponent a lot more easily and then strike at the Spino’s neck. One bite would either kill it or disable the Spino so much that it would be too weak to fight and then a few more bites from T. rex would be enough to finish the Spinosaurus.

Whilst the Spino could certainly kill T. rex, I simply see T. rex being able to kill the Spino much more easily and therefore I am going to have say that Tyrannosaurus would be the more likely winner.

So then in conclusion as to who would win in a fight with Tyrannosaurus and Spinosaurus, I see it like this

In the wild Tyrannosaurus and Spinosaurus would have a 50/50 chance of killing each other.

In a Dinosauroid arena match however

23 ton Spinosaurus vs 9 ton Tyrannosaurus, 100 percent in favour of the Spinosaurus.

Tyrannosaurus that is slightly heavier or the same size in weight as Spinosaurus, 80 percent in favour of the Tyrannosaurus.

4 legged 23 ton Spinosaurus against a 21 ton Tyrannosaurus, 70 percent in favour of the Tyrannosaurus.

21 ton Tyrannosaurus against a 23 ton Spinosaurus, 60 percent in favour of the Tyrannosaurus.

The Tyrannosaurus wins in more scenario’s, but Spinosaurus is a worthy foe at least and it would most certainly be capable of killing a T. rex.

Also bare in mind the only time that I feel there would ever be an absolute 100 percent chance of one animal killing the other would be in Spinosaurus’s favour.

Ultimately however Tyrannosaurus I simply feel at the end of the day was a superior predator and in most scenario’s would kill its rival.