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Top 10 Slowest Dinosaurs Of All Time

Dinosaurs do not have to be fast to be interesting and cool creatures; in fact, there are many dinosaurs that once existed that were on the slower side, but this means that they had very unique and interesting ways of keeping themselves safe from predators. The slower the dinosaur, the more interesting they were. So, here are the top 10 slowest dinosaurs of all time.

There were many dinosaurs that existed throughout the world, but not all of them were fast. Here are the top 10 slowest dinosaurs of all time:

  1. Stegosaurus
  2. Argentinosaurus 
  3. Ankylosaurus
  4. Euoplocephalus
  5. Kentrosaurus
  6. Lambeosaurus
  7. Brachiosaurus
  8. Albertosaurus
  9. Iguanodon
  10. Apatosaurus

These dinosaurs are really slow, but they did adapt many different techniques to help them survive in the harsh time that they did, with predators roaming around every tree. Let us go more in-depth into these dinosaurs, and let us see exactly how fast they could go.

The Ten Slowest Dinosaurs 

There have been many dinosaurs that have roamed the earth and through many different time periods too. These dinosaurs came in all shapes and sizes, which means they had different speeds as well. 

There have been multiple articles going around about which dinosaurs were the fastest, but very few on the slowest dinosaurs. Just because they were slow does not mean they were not interesting and worth people’s time. So, let us show some appreciation for the slowpokes; here are the top 10 slowest dinosaurs of all time.

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1. Stegosaurus Dinosaur

The Stegosaurus was from the genus of herbivorous thyreophoran dinosaur. This dinosaur existed in the late Jurassic period, from about 155 to 150 million years ago, in Portugal and the western United States. 

This dinosaur was around 29.5 ft (9 meters) in length and measured about 13 ft (4 meters) in height when it reached its full size at adulthood. This dinosaur weighed in at a measly 3 tons (6613 lbs), which was quite light for dinosaurs.

The Stegosaurus was a large and heavily built dinosaur, it had a rounded back with long hind limbs and shorter forelimbs, and their tails were held high up into the air. This dinosaur was one of the most recognizable dinosaurs that existed due to its tail that was tipped with spikes and broad upright plates that lined its back. 

Their spiked tails were probably used in defending off predators, and the plates along its back have been suggested to be for show and thermoregulatory processes. The Stegosaurus had a low brain-to-body ratio, which means this dinosaur may not have been the most intelligent dinosaur there ever was. 

This dinosaur was ready for defense; however, it could not move very fast and is known as the slowest dinosaur of its time.  The Stegosaurus could only reach the magnificent speed of 4 mph (7 kph). 

2. Argentinosaurus Dinosaur 

The Argentinosaurus dinosaur was from the genus sauropod dinosaur the existed in the late Cretaceous period in, what is now known as, Argentina. This dinosaur is considered to be one of the largest land animals known to walk the earth

This gigantic creature measured between 100 to 130 ft (30 to 40 meters) in length, with a height of about 52 ft (16 meters), and weighed an enormous 50 to 100 tons (100000 to 200000 lbs).

The femur of this gigantic dinosaur measured 8.2 ft (2.5 meters) long, with a circumference of around 3.9 ft (1.18 meters). One single vertebra of this dinosaur was about 63 inches (159 cm) in height and 51 inches (129 cm) in width. This dinosaur was a herbivore that could reach the tops of the highest trees on earth. 

Unfortunately, the size of this enormous creature did affect its speed quite a bit as this dinosaur could only reach about 4.3 mph (7 kph).  

3. Ankylosaurus Dinosaur

The Ankylosaurus is an armored dinosaur that existed until the very end of the Cretaceous period, which was between about 68 to 66 million years ago and was mainly found in the western parts of North America. 

There have only been a handful of fossils found of this dinosaur, but the largest one was estimated between 20 to 26 ft (6 to 8 meters) in length and was about 5.6 ft (1.7 meters) tall at the hip

These dinosaurs weighed between 4,8 and 8 metric tons (10582.2 to 17637 lbs). The Ankylosaurus was quadrupedal (it walked on four legs); it had a broad and robust body. The head of this dinosaur was wide and carried low to the ground, and it had two horns that protruded from the back of its head. 

The Ankylosaurus was one of the slowest dinosaurs to exist

The Ankylosaurus was a herbivore and mainly grazed on plants that grew close to the ground. One of the most well-known and prominent features of this dinosaur is its armor that was comprised of plates and knobs of bone, scientifically known as osteoderms, that were embedded in the dinosaur’s skin. 

These osteoderms ranged in size but can be from 0.39 inches (1 cm) in diameter and 1.16 ft (35.5 cm) in length—these plates were hollowed on the bottom side and had thin walls.

This dinosaur was like a walking tank, and this showed in its speed too. This dinosaur could only reach about 4.9 mph (8 kph) when running.

4. Euoplocephalus Dinosaur

The Euoplocephalus dinosaur is from the genus ankylosaurian dinosaurs that existed in the late Cretaceous period in Canada. This dinosaur could measure 19.6 ft (6 meters) in length and was about 6.5 ft (2 meters) in height and weighed around 2 tons (4409 lbs) when it reached adulthood.

The body of the Euoplocephalus was quite flat and wide and was very low to the ground. This dinosaur had four short but very sturdy legs, with a short head that had a horned beak that allowed it to bite off bits of plants that this dinosaur ate. 

The Euoplocephalus was covered in bony plates that it used as armor; these plates were quite large, and they were high-ridged oval scutes, and its neck was protected by two rings that were made from bone. The scutes were quite small, measuring 5 millimeters in diameter. However, the dinosaur has hundreds of them covering their body to form their armor. 

The head of the Euoplocephalus was also covered in ossicles; these may have fused the normal elements of the skull, which could have made their sutures (connections) fade. This dinosaur also had a strong tail that ended in a heavy club; this added to the dinosaur’s defense.

This dinosaur was relatively short and had a low profile, which means that it could not move very fast and only got up to speeds of 4.9 mph (8 kph).

5. Kentrosaurus Dinosaur

The Kentrosaurus dinosaur was from the genus of stegosaurian dinosaurs that lived in the late Jurassic period, about 154 to 153 million years ago, in Tanzania. This dinosaur was approximately 16 ft (5 meters) in length and about 6.5 ft (2 meters) in height and weighed in at 1 ton (2000 lbs) when it was fully grown.

The Kentrosaurus was quadrupedal (walked on four legs), it has a small head that was elongated, and it had a beak that it used to bite at plants with. The Kentrosaurus had a double row of small plates that ran down its back and neck. These plates would go from plates to spikes from the dinosaur’s hip and would extend all along the tail. 

The spikes that were on the dinosaur’s muscular tail were much larger than the rest of the spikes, and the Kentrosaurus would use these sharp spikes for defense. The tail of this dinosaur was just over half its overall length, meaning that it had a far reach and could defend itself from a distance. This dinosaur also had one large spike on each of its shoulders to help defend it against any attacks. 

This dinosaur was small, light, and close to the ground; this low profile did not help its speed, though. This dinosaur could only reach about 4.9 mph (8 kph).  

6. Lambeosaurus Dinosaur

The Lambeosaurus is from the genus called the hadrosaurid dinosaur, and it lived in the late Cretaceous period, which was about 75 million years ago, in North America. This dinosaur measured at 23 ft (7 meters) in length and 6.5 ft (2 meters) in height and weighed about 6 tons (12000 lbs).

This dinosaur is best-known for its distinctive cranial crest that resembled a hatchet and was right on the top of its head. The Lambeosaurus could walk on both two and four legs; this depended on the terrain it was in and whether they were eating plants that were higher up or on the ground.

The Lambeosaurus had a long tail that was held stiff above the ground with the aid of ossified tendons that were in the tail. Scientists have suggested that this dinosaur had quite thin skin with polygonal scutes that were on its neck, tail, and torso. 

The Lambeosaurus was a gentle herbivore, and it has been speculated that the crest on its head was used for show, display for breeding, and possibly for defense. 

This docile creature could move at a speed of only 6 mph (10 kph), which was fast enough for this dinosaur to survive with little armor to protect it. 

7. Brachiosaurus Dinosaur


The Brachiosaurus dinosaur was a sauropod dinosaur that lived in the late Jurassic period, which was about 154 to 153 million years ago, in North America. This dinosaur was ranged between 59 and 69 ft (18 and 21 meters) in length and weighed a whopping 58 metric tons (127868 lbs) when it reached adulthood.

The height of this dinosaur could range from 30 ft (9 meters) to 43 ft (13 meters). This was a gigantic dinosaur. 

This dinosaur had a long neck that was disproportioned to the rest of its body, and it had quite a small skull for its size, but this was typical for their genus of sauropods.  

The Brachiosaurus was a herbivore and used its long neck to reach the top of high trees, and scientists have speculated that this dinosaur may have used its long, sturdy tail as a leg to balance itself on when trying to reach the tops of tall trees.

The legs of this dinosaur were different sizes, with its front arms being longer than its back legs. We are yet to discover why their front arms were longer; maybe it gave them an advantage over other dinosaurs in certain aspects.

Because of the enormous weight and size of this dinosaur, you may be thinking that this massive creature would have been the slowest dinosaur to ever walk the earth. On the contrary, the Brachiosaurus could reach speeds of up to 11 mph (18 kph).  

8. Albertosaurus Dinosaur

The Albertosaurus dinosaur is from the genus tyrannosaurid dinosaur that lived during the late Cretaceous period, which was about 70 million years ago, in the western parts of North America. This dinosaur grew to about 26 to 33 ft (8 to 10 meters) and could have weighed in at 2.5 tons (5000 lbs).

This dinosaur was bipedal (walked on two legs) and balanced itself using its strong tail, and the Albertosaurus was a predator, with one of its most famous relatives being the T-Rex. The Albertosaurus had small front arms that had hands with two fingers on each. It had a massive head for its size that was filled with dozens of razor-sharp teeth. 

The bite force of the Albertosaurus was around 3413 Newtons. This was not as strong as the t-Rex, but it was perfect for Albertosaurus to take down its prey. This dinosaur also had some short bony crests that were just above their eyes; it is believed that these were brightly colored and could have been used to help attract a mate.

This dinosaur was probably at the top of the food chain of its ecosystem and preyed on many different dinosaurs. These dinosaurs had scales that started out at the size of a pebble but gradually become larger and hexagonal in shape as they moved up the body. 

Even though the Albertosaurus was a predator, it could not move as quickly as its relatives; this dinosaur could only reach speeds of up to 13 mph (21 kph).

9. Iguanodon Dinosaur

The Iguanodon dinosaur was from the genus ornithopod dinosaur and existed between the Mid-Jurassic and the late Cretaceous period all around the northern hemisphere. These dinosaurs measured between 32 to 42 ft (10 to 13 meters) long and 9.8 ft (3 meters) in height and weighed about 3 tons (6000 lbs).

These dinosaurs had skulls that were large, tall, and narrow, and they had beaks that they used to strip plants with. The arms of the Iguanodon were robust and long, and their hands had three fingers that could bear weight and were quite flexible.

The Iguanodons thumbs were spikes that protruded outward, away from the other three fingers; the function of these spikes has been a topic of debate, and it has been suggested that they may have been used for foraging or for defense.

These dinosaurs’ legs were not built for running; however, they still managed to get to a good speed reaching about 14.9 mph (24 kph) at its fastest.

10. Apatosaurus Dinosaur


The Apatosaurus was from the genus herbivorous sauropod dinosaur and existed in the late Jurassic period in North America. This dinosaur was on average between 69 and 75 ft (21 and 22 meters) in length and could weigh between 16 and 22 tons (32000 and 44000 lbs).

The Apatosaurus was a very large dinosaur with a long neck; it was also quadrupedal (walked on four legs), and it also had a long tail that was relatively thin for its size; it was more whip-like. The forelimbs of the Apatosaurus were shorter than the hindlimbs; we are still unsure of why they were. 

The skull of this dinosaur was quite small for its size too, and its jaw was imbedded with spatulate teeth, which were perfect for its diet of plants. 

Even though this dinosaur was quite large, its size did not slow it down much, and it could reach speeds of 14.9 mph (24 kph).


There were many dinosaurs that roamed the earth millions of years ago; they come in all sizes and shapes. However, their sizes did not always affect how fast they could run, as one of the smallest dinosaurs on this list was slower than one of the largest. 
These dinosaurs are all interesting in their own right and have many unique features; they should not be overlooked just because they were slow.

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