In this article, we’ll discuss 11 of the heaviest dog breeds. Measurements will be based on the American Kennel Club (AKC) and Federation Cynologique Internationale (FCI) metrics. We will determine rankings according to breeds’ average weight rather than their maximum weight. However, we’ll still cover cases of exceptionally massive specimens, especially near the end of the list. Here’s a list of the world’s 11 heaviest dogs. 

#11: Tibetan Mastiff

The Tibetan Mastiff is a large breed from East Asia. Despite its name, it’s not a true mastiff, nor is it directly related to the mastiff. They frequently used to guard Tibetan monasteries, which is how they got their name. Found throughout Tibet, India, Mongolia, Nepal, Bhutan, and Pakistan, herders used the dogs to protect livestock from predators. Males weigh from 90 to 150 pounds, while females typically measure 70 to 120 pounds. They sport long double coats in various colors, from black to tan, red, and gray. A hardy breed, Tibetan Mastiffs can survive in harsh climates and conditions. Bred initially as nocturnal sentries, they tend to sleep during the day and remain active at night. Known for their stubbornness and intelligence, they require obedience training from a young age; otherwise, they may overpower their owner. 

#10: Kangal Shepherd Dog

Also known as the Anatolian Shepherd Dog in the United States, the Kangal Shepherd Dog is a large breed from Turkey. The breed remains popular in its native region of Sivas, where herders bred it to protect livestock from large predators. Male Kangals grow between 110 to 150 pounds, while females weigh between 80 to 120 pounds. Kangals grow a short coat, most often occurring in fawn or sable coloring. In recent years, Kangals have been introduced to countries such as Namibia as Kenya. In these countries, herders continue to employ the breed as a working dog to protect animals from lions, cheetahs, and other big cats. Kangal Shepherd Dogs enjoy a fearsome reputation, and many specimens inherit strong protective instincts. Therefore, they require an experienced trainer who can help to control their independent nature. 

#9: Newfoundland

The Newfoundland is a heavy breed of working dog from Newfoundland, Canada. Initially bred by fishermen in the area, they excel at water rescue due to their webbed paws and excellent swimming abilities. Male Newfoundlands usually measure between 130 to 150 pounds, while females measure 100 to 120 pounds. However, some specimens can grow exceptionally heavy, with some Newfoundlands like the immense Boomer weighing up to 180 pounds. Often confused for Labradors, Newfoundlands sport a long, shaggy double coat and a much thicker build. They come in a range of colors, although black remains the most common. Known for their loyalty and calm disposition, as well as strength, they make excellent family dogs. However, their fondness for water and mud can make them a handle to deal with and clean up after. 

#8: Neapolitan Mastiff

A close relative to slightly smaller Cane Corso, the Neapolitan Mastiff is a genuine member of the Mastiff family. Bred initially in the mid-20th century, the Neapolitan Mastiff can trace its ancestry back to the ancient guard dogs of central Italy. Males typically weigh between 130 to 150 pounds, while females weigh from 110 to 130 pounds. However, huge specimens can weigh up to 220 pounds. Neapolitan Mastiffs sport extremely wrinkly faces and jowls and typically appear black or gray. Although they require little grooming, they exhibit a tendency for excessive drooling. They frequently act mistrustful of strangers thanks to their training as guard dogs, and many inherit a natural protective instinct. While they don’t require much exercise, obedience training is a must due to their large size. 

#7: Irish Wolfhound

The Irish Wolfhound belongs to the sighthound family of dogs that hunt based on their keen eyesight and speed. Famed for their large size and power, Irish Wolfhound rank among the tallest dogs in the world. In addition to their height, they also tip the scales as one of the heaviest dogs. Males weigh at least 120 pounds and frequently reach 160 pounds or more. Although females measure smaller, they weigh at least 105 pounds and can grow up to 130 pounds. In addition to their roles as pursuit animals, herders also used Irish Wolfhounds to protect livestock from wolves. They sport a coarse, straight double coat, with gray, fawn, black, and white among the most common colors. Known for their quiet and intelligent nature, Irish Wolfhounds usually act friendly towards people, including strangers. 

#6: Caucasian Shepherd Dog

Also known as the Russian Bear Dog, the Caucasian Shepherd Dog represents a genuinely massive breed. They originate from the Caucasus region, most notably Georgia, Azerbaijan, Armenia, and Southern Russia. Herder bred them to guard livestock against predators such as wolves and bears. Today they continue to work as guard dogs for families and in prisons and remain popular among bear hunters, which is where they get their name. Males weigh at least 110 pounds and grow up to 170 pounds. However, some males can weigh over 200 pounds. Meanwhiles, females weigh at least 99 pounds. Due to their history in hunting and as guard dogs, Caucasian Shepherds rank as one of the world’s most protective and aggressive breeds. In addition, they sport one of the most potent bite forces of any breed, measuring between 550-700 psi. 

#5: Leonberger

A breed of giant mountain dog, Leonbergers get their name from the city of Leonberg in Germany. Primarily used as water rescue dogs, Leonbergers are famous for their large, muscular frame. Males weigh between 120 to 170 pounds, while females typically weigh between 110 to 135 pounds. That said, massive males can easily weigh over 200 pounds. Leonbergers sport a long, luxurious double coat and a thick mane on their neck. They come in several colors but often appear yellow, red, red-brown, or sand-colored with a black mask. Thanks to their well-socialized and insensitive nature, they make great family dogs and adapt well to the presence of children. However, due to their large size, they still require proper training and control. 

#4. Great Dane

One of the most recognizable breeds in the world, the Great Dane is one of the tallest and heaviest dogs globally. In its native Germany, Great Danes can trace their history back to the Middle Ages, when nobility used them for hunting deer and other large game. Males typically weigh 140 to 175 pounds, while females weigh from 110 to 140 pounds. However, exceptionally tall Great Danes can easily weigh much more, with the biggest weighing up to 240 pounds. They typically appear fawn or brindled, although other colors include the black and white Harlequin Danes, blue, and grey Merle Danes. Despite their large size, many owners consider Great Danes as gentle giants. They love receiving physical attention and can act quiet affection and loving to their owners. 

#3. Saint Bernard

The Saint Bernard is a large breed of rescue dog from the Western Alps in Italy and Switzerland. Originally bred around the mid-1600s, Saint Bernards grew famous for saving people from avalanches and other Alpine accidents. Males typically weigh between 140 to 180 pounds, while females weigh from 120 to 140 pounds. That said, they can grow much heavier. For example, a massive Saint Bernard named Benedictine ranks as the heaviest dog ever, weighing in at an insane 357 pounds. Although they can grow to enormous sizes, Saint Bernards usually inherit a gentle and passive temperament. They tend to get along well with people and other dogs, although they may pose a danger to small children due to their size. 

#2: Spanish Mastiff

The Spanish Mastiff of Mastin Espanol is a large breed of working dog from Spain. Originally bred as guard dogs and livestock guardians, Spanish Mastiffs rank as one of the tallest and heaviest dogs in the world. Males can weigh up to 200 pounds, while females weigh at least 140 pounds. Although the most common coat color is fawn, they also can appear brindle, black, or red-colored. Spanish Mastiffs possess a calm, dignified nature, although they can act aloof or mistrustful of strangers. In addition, they may act aggressively toward other dogs. Thanks to their large size and powerful bark, they make excellent watchdogs and guard dogs. While they require strict training, they respond well to positive motivation, particularly when food is involved. 

#1. English Mastiff

On average, the English Mastiff ranks as the heaviest dog in the world. Known simply as the Mastiff in its native home, the United Kingdom, the English Mastiff can grow to immense sizes. Males typically weigh between 150 to 230 pounds, while females weigh from 120 to 170 pounds. That said, English mastiffs frequently weigh in the mid and high-200s, with the heaviest English Mastiff ever weighing an astonishing 315 pounds. English Mastiffs typically appear fawn-colored and sport a distinctive black mask. In the mid-20th century, they almost went extinct, with only 12 purebred specimens remaining after World War II. Thankfully, the breed rebounded and now enjoys popularity around the world. Despite their immense size, owners generally praise English Mastiffs for their noble and generous temper. 

World Record! Meet The Heaviest Dog in the World

According to Guinness World Records, the heaviest dog ever recorded was an English Mastiff named Zorba. In November 1989, the massive Zorba was recorded as weighing a whopping 330 pounds. In addition to tipping the scales and setting weight records, Zorba was also incredibly tall and long. Measuring from floor to shoulder, Zorba towered 37 inches tall – that’s 7 inches more than the typical Mastiff. In terms of length, Zorba was 8 feet and 3 inches long – that’s about the length of a king-sized bed!