Rottweiler in grass

What Are the 10 Most Aggressive Dog Breeds

One of the biggest concerns that owners – to – be have when choosing a dog breed is whether or not they have increased aggression, especially for those with families with younger children. If you are looking to get a new dog and don’t know which breed is deemed the “safest” then maybe this list will help you choose which one to get.

Keep in mind that exceptions do exist and not every dog you meet whose breed is listed below means that they are going to attack you. Before we take a look at the list, we should first define what canine aggression is.

How is canine aggression described ?

Canine aggression is described as a dangerous behavior towards another individual, be it human or just another dog. Some of those aggressive behaviors include biting, barking, lunging, snarling and similar. There are many reasons for these behaviors to erupt such as territorial defensiveness and protectiveness, social anxiety, fear, etc.

You may also be interested in: The best small calm dog breeds

How the dog breeds on the list were ranked for aggression ?

The breeds we have listed below are so because they have some of the lowest overall passing rates in the temperament test that was conducted by the American Temperament Test Society. That being said they are sorted in order from the lowest passing percentage rates that most commonly displayed signs of panic, aggression or even shyness during the test.

Even though there are breeds that have even lower passing percentage scores than those that are listed in this article, the decision was to make the list limit to 10 because those are the breeds that are commonly referred as aggressive and/or dangerous.

Finally, here is the list of the 10 most aggressive dog breeds that first time owners should avoid, with their overall passing rates included.

The 10 “Most Aggressive” Dog Breeds

  1. Chihuahua
  2. Dachshund
  3. Chow Chow
  4. Doberman Pinscher
  5. Dalmatian
  6. Rottweiler
  7. Jack Russell Terrier
  8. German Shepherd
  9. American Staffordshire/Pit Bull Terrier
  10. Siberian Husky


  1. Chihuahua

Chihuahuas are by far the smallest dog breed registered with the American Kennel Club, AKC for short. Chihuahuas are also thought to be the smallest dog breed in the world. Usually regarded as a part of the “toy” group of dogs, chihuahuas usually weigh anywhere from four to six pounds, they can have either short or long hair of any color whether solid, marked or splashed.


Originating from the Mexican state of Chihuahua, which is coincidentally who they got their name, this breed is considered to be one of the oldest ones from America as it was first introduced to Europe by the colonizer Christopher Columbus.

Loyalty and devotion to their owners is a primary characteristic of chihuahuas, but that loyalty limits itself to just one or two people. All of that devotion isn’t all positive though, it can grow to a point of jealousy and they may bite or snap at anyone that dared to come too close to their owner. They aren’t known to be very child friendly and are very temperamental, and because they do not like strangers, they may often bark which can prove useful as an alert.

Temperament Test Results

Tested Passed Failed Passing Percentage
46 32 14 69.6%


  1. Dachshund

This breed is categorized as a part of the “hound” group by the American Kennel Club. Dachshunds weigh anywhere from 8 to 32 pounds and they can have either long or short hair of any natural color.

Dachshunds originate from Germany, specifically in the 17th century and were primarily used for hunting badgers. However, at the end of World War I, they were almost extinct. Luckily the populations have since recovered and as of the present they are one of the most popular dog breeds out there.


Like other dogs of this size, dachshunds are also susceptible to the so called “small dog syndrome”. That basically means that they make up for their small size with a pretty big attitude. This unfortunately can lead to many problems and various behavioral issues in the dog.

It can be combated if the dog is socialized at an early age, but no matter what they won’t tolerate any rough play and will resort to an attack. Keep in mind to take extra precaution if you already own smaller pets such as rats, mice and/or hamsters, as this breed has a very strong natural hunting instinct towards this type of animal.

Temperament Test Results

Tested Passed Failed Passing Percentage
48 33 15 68.8%


  1. Chow Chow

This breed is listed as a medium sized dog in the “non sporting” group by the American Kennel Club. Chow Chows typically weigh anywhere between 45 to 70 pounds full grown and they have characteristically long and thick coats that can come in various colors such as black, cream, blue, cinnamon and red.


Fun fact: the exact origin of Chow Chows is currently unknown and it is widely believed that they originated from either China or Mongolia thousands of years ago and they were primarily used as hunters and herders. During the 20th century they became quite popular in the US when President Calvin Coolidge kept one as a pet.

Chow Chow is known for their dominant personality and the fact that they can become quite assertive at times. Just because of this character trait, they are not recommended for first time dog owners. They need stern training and guidance if you want to raise a good mannered Chow Chow. Additionally, they have decreased peripheral vision, so they do get startled easily.

Temperament Test Results

Statistics from the American Temperament Test Society (ATTS)
Tested Passed Failed Percent That Passed
99 71 28 71.7%


  1. Doberman Pinscher

Doberman Pinschers are listed as a medium sized dog in the “working” group by the American Kennel Society. This breed weighs anywhere around 70 to 90 pounds and they have a characteristically thick, glossy and short haired coat that can be red, black, fawn or blue in color.


The Doberman Pinscher originates from Germany and a man by the name of Karl Louis Doberman takes the credit for their creation and development. Karl Louis Doberman worked as a tax collector and because of that he wanted a dog that he could take with him for some protection on his visits to more dangerous areas, so he developed one.

This breed is widely known for their intelligence and they are used as guard dogs and police dogs. Doberman Pinschers have a strong protective instinct towards their masters, however, if they are raised by good owners as well as trained and disciplined correctly, they can be good with children and other dogs as well!

Temperament Test Results

Statistics from the American Temperament Test Society (ATTS)
Tested Passed Failed Percent That Passed
1,733 1,371 359 79.1%


  1. Dalmatian

Classified by the AKC as a medium sized dog in the “working” group, dalmatians range in weight from around 45 to 60 pounds and have a short, dense and glossy coat that is white speckled with brown or black spots.


The origins of Dalmatians have not been confirmed. Many similar dogs are depicted running behind chariots in paintings that have been found on the walls of some Egyptian tombs, and since the late 18th century they have been used as a type of carriage dog to guard both the passengers and the cargo of the carriage.

This breed needs to be socialized early, if you want them to behave good around children. If they are not given enough attention by their owner, they can develop some behavioral problems. Since they are very energetic dogs, they need to have a lot of exercise and play time to release all of that extra energy.

Temperament Test Results

Tested Passed Failed Percent That Passed
358 291 59 81.3%


  1. Rottweiler

Rottweilers are listed as a large sized dog in the “working” group by the AKC. This breed’s size ranges from around 85 to 130 pounds in weight and have short, dense coats that are usually black with mahogany or rust markings around specific areas.

Rottweiler in grass

They get their name from the small town of Rottweil located in Germany. This breed was first known as the “Rottweil butcher’s dog”, which was later shortened to the familiar Rottweiler. In the past they were used for cattle herding and bear hunting, among many other things, and later on they got popular in the US as guard dogs, many of them utilized by the army and police forces.

Rottweilers can be a pretty aloof breed and they generally do not get along well with strangers at first, but they are also very loyal and protective of their owners and they tend to defend their home areas firmly. Good natured with children, but due to their size and high energy level, it is not recommended to keep them around infants or toddlers.

Temperament Test Results

Statistics from the American Temperament Test Society (ATTS)
Tested Passed Failed Percent That Passed
5,866 4,954 915 84.5%


  1. Jack Russell Terrier

Unfortunately, due to opposition from the breed’s parent society – The Jack Russell Terrier Club of America (JRTCA), the American Kennel Club does not recognize the Jack Russell Terrier breed. Because of this, the AKC recognizes the Parson Russell Terrier instead, which is basically the same breed with some minor differences.

jack russel terrier

They are small sized dogs that can weigh anywhere between around 14 to 18 pounds and they come in primarily white with black or tan markings. This breed’s coat can be short haired, long haired and even broken, which means coats that have both long and short hair.

The Jack Russell Terrier originates from England where they were used for hunting foxes, but they also have been used to hunt both badgers and groundhogs.

This breed tends to be very energetic and stubborn, as they have little patience and are known to not be very tolerant of children. Many experts actually recommend that families with younger children, as in toddlers and infants, either wait for them to be older before getting this breed, or get a totally different one.

Temperament Test Results

Statistics from the American Temperament Test Society (ATTS)
Tested Passed Failed Percent That Passed
68 58 10 85.3%


  1. German Shepherd

German Shepherds are medium in size and they are included in the “herding” group classified by the AKC. They can range in size from around 70 to 85 pounds and have a coat that’s usually a mix between black, gray, brown and tan colored fur.


The German Shepherd breed originated from Karlsruhe in Germany, in the 1800s, and during Word War I they were predominantly used as military dogs, both by the German and the French armed forces. This is a very intelligent breed and they were the first to be used as guide dogs for the blind. German Shepherds are also frequently utilized in search and rescue teams and as police and narcotic dog.

This breed has quickly grown in popularity in America. German Shepherds tend to not like strangers, so they make excellent guard dogs! While they do appear on many aggressive dog lists, they are generally good with kids of any ages. If you don’t specifically train them as guard dogs, they tend to be more approachable for people.

Temperament Test Results

Statistics from the American Temperament Test Society
Tested Passed Failed Percent That Passed
3,318 2,827 494 85.2%


  1. American Staffordshire/Pit Bull Terrier

This breed is a medium sized dog that is included in the “terrier” group classified by the American Kennel Club and they usually range in sizes from around 55 to 65 pounds. They can be referred to as either an American Staffordshire Terrier or an American Pit Bull Terrier.


This breed originated from the Staffordshire region in England, that’s how they got their name. They were firstly specifically designed to be used as guard dogs or dogfighting, hence why they have that strong and stocky frame. Once the breed was brought over to America and dogfighting was completely banned, the second strain of this breed was in development. The newer variation had a milder temper and they had a significantly smaller frame than before. This strain is known as the American Pit Bull, and this particular strain is known to be extremely loyal and protective of its family.

The pit bull is known to get along very well with children and is patient with them, however if you are unsure about a pit bull’s pedigree, it’s recommended to do a backroad check before choosing it as your pet.

Temperament Test Results

Statistics from the American Temperament Test Society (ATTS)
  Tested Passed Failed Percent That Passed
American Pit Bull Terrier 913 798 115 87.4%
American Staffordshire Terrier 716 610 106 85.2%


  1. Siberian Husky

Siberian huskies are medium sized dogs classified in the “working” group by the American Kennel Club. They can weigh anywhere between 35 to 70 pounds and they have medium length hair and a double coat. They come in a variety of colors: red and white, black and white, gray and white, or even silver.


The Siberian Husky originates from Siberia, hence the name, where they were used to pull sleds in cold climates. They were also utilized as rescue dogs.

There are not any definitive studies that prove that huskies are specifically aggressive breed, however, they have appeared on many lists of aggressive dogs, so that’s why they are ranked on this one as well. Huskies tend to be territorial though, and they do not always get along swimmingly with other dogs, but they are good with kids.

Huskies are a high personality dog breed with a loud voice, so before adopting definitely do some research whether on the internet or through books. You can even visit a shelter that has some huskies for adoption to see how they behave.

Temperament Test Results

Statistics from the American Temperament Test Society (ATTS)
Tested Passed Failed Percent That Passed
304 264 40 86.8%


What to take away from the results of the Temperament Test

 We advise to take the percentages that were provided by the American Kennel Society with a certain grain of salt, since the number of dogs they have tested per breed is not the same. Take for an example, when the ATTS was conducting the test on Rottweilers, over 5000 of them were tested, while on the other hand only 46 Chihuahuas were put though the same testing. Because the sample sizes differ so much, the percentages that have come out of the tests may not wholly represent each and every breed’s aggression.

  • How the ATTS did the testing

According to this society, the test they conducted focuses on and measures the different aspects of temperament such as stability, shyness, aggressiveness, and friendliness while also testing the dog’s instinct for protectiveness towards its handler and self preservation when facing a threat.

More specifically, the test simulates a walk through the neighborhood where the individual dog encounters many situations ranging from neutral, friendly and threatening. A bunch of strangers approach the handler, one by one, and surprising noises are emitted from secret locations. The goal of the testing is to study how the dog reacts to noises, people, and its surroundings.

  • How they determine the passing rate.

The listed percentage underneath each dog breed is the thing that indicates the number of dogs that have passed the temperament test divided by the total number of dogs that were tested for that breed. For example, 46 Chihuahuas were tested, and only 14 failed, which makes the passing percentage for Chihuahuas the number of dogs that passed – 32 divided by the total number of dogs tested – 46, or 69.9 percent in short.

They determine a failure if the dog shows any of the following signs:

  • Unprovoked aggression
  • Exhibiting panic without recovery
  • Strong avoidance.
  • Some shortcomings to consider

Solely because “strong avoidance is considered a failure by the ATTS, the test may not accurately isolate the trait of aggression alone. Also, since the number of dogs that were tested per breed varies dramatically, the sample size isn’t consistent throughout the study, the passing rates for breeds that had a larger sample size may be much more reliable than the passing rates of those breeds that had a smaller sample size tested.

What is the most dangerous dog breed?

If you ask any dog trainer what the most aggressive dog breed is, they will most likely end up not saying a specific breed. One such opponent of this “breed labeling” is the celebrity dog behaviorist Cesar Milan. He strongly believes that the most dangerous dog in the world is the one that has been made that way by a human.

Cesar Milan’s views directly reflect on the importance of seeking out the truth beyond the provided numbers and statistics. For example, anyone that has ever owned a pit bull can attest to its gentle nature and overly affectionate behavior when raised with love and care by its owners, despite the infamy of them being supposedly vicious.

Any dog is a reflection of the environment it was raised with plus the training it was given. That means that if a certain is widely considered to be aggressive and have problematic behavior, this can point to the type of person that usually owns that specific breed. Take for example, German Shepherds tend to be owned by people that train them to be guard dogs, protecting their property, and that explains their hostile behavior towards strangers.

The conclusion: Not one breed is inherently aggressive

The list provided in this article has been made by compiling information from a great many sources. However, just because a certain breed has a ranking on this list it does not mean that it will not make a good family pet with the right owners and correct amount of training.

Since training, or lack thereof, and how a dog has been treated previously can make a huge impact on its personality, doing any kind of background check on the dog before adopting it is always key for a positive outcome in the end.

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