Biggest Dog in the World: Tallest, Heaviest & Largest Breeds

Anyone who’s ever met a Great Dane up close knows the feeling: neck craned up, a moment of disbelief. The title of biggest dog depends on whether you measure height, weight, or breed averages — here are the records.

Tallest dog ever (Great Dane Zeus): 44 inches (111.8 cm) at the shoulder ·
Heaviest dog ever (Mastiff Zorba): 343 lbs (155.6 kg) ·
Tallest breed (Irish Wolfhound): Average 30–34 inches at shoulder ·
Heaviest breed (English Mastiff): Average 160–230 lbs ·
Current tallest living dog: Approximately 40+ inches (Great Dane)

The following table summarizes the official record holders.

What is the largest dog on Earth?

Defining “largest”: height versus weight

The question sounds simple, but “largest” means different things to a Great Dane owner and a Mastiff breeder. Height at the withers (the ridge between the shoulder blades) is the standard for tallest-dog records. Weight, on the other hand, determines the heaviest. The American Kennel Club (purebred registry and breed authority) treats breed size separately from individual outliers: a breed like the Irish Wolfhound averages taller than a Mastiff, but a single Great Dane can tower over both.

The Guinness World Records holders

Guinness World Records has officially recognized several dogs in each category. The tallest dog ever recorded is Zeus, a Great Dane from Michigan, who measured 44 inches (111.8 cm) at the shoulder in 2011. In 2022, another Great Dane also named Zeus took the tallest living title at 1.046 metres (3 ft 5.18 in) (Guinness World Records, official record authority). The heaviest dog ever recorded remains Aicama Zorba of La-Susa, an English Mastiff who weighed 343 lbs (156 kg) in 1989, as reported by USA Today (national news outlet).

How size is measured in dogs

For height, Guinness measures from the floor to the withers with the dog standing on all fours. Weight is taken on a veterinary scale under supervision. PetPlace (pet-care resource) notes that giant breeds generally range from 75 to over 120 pounds, but record-holders far exceed these averages.

What is the tallest dog breed?

Irish Wolfhound: the traditional tall breed

The Irish Wolfhound is recognized by the American Kennel Club (purebred breed authority) as the tallest breed of dog. Males average 32–34 inches at the shoulder, and females 30–32 inches. Originally bred as war dogs and wolf hunters, they combine height with a lean, athletic build. For more on size comparisons in the animal kingdom, see When Did Dinosaurs Go Extinct?

Great Dane: the record-holding tall breed

Great Danes are the breed most associated with tallest-dog records, as BBC Newsround (children’s news service) points out — Kevin, a Great Dane from Iowa, was reported as the world’s tallest dog in 2024 at 3 ft 2 in (96 cm). While the breed standard calls for a minimum height of 30 inches for males, individual Danes routinely break 36 inches.

Other tall breeds: Scottish Deerhound, Borzoi

The Scottish Deerhound and Borzoi both reach heights of 28–32 inches, placing them among the tallest sighthounds. However, neither breed has approached the record heights of the Irish Wolfhound or Great Dane in official Guinness competitions.

The choice between these two breeds depends on whether you prioritize height records or breed standard.

What are the top 5 largest dog breeds?

Here is a comparison of the top five largest breeds.

The pattern: no single breed dominates both height and weight. Great Danes and Irish Wolfhounds lead in height; English Mastiffs and Saint Bernards lead in mass. AKC (breed registration authority) emphasizes that “largest” should be considered within breed groups rather than as a single ranking.

What this means: if you want the tallest breed, choose an Irish Wolfhound; if you want the heaviest breed, choose an English Mastiff; if you want a dog that might break a record, choose a Great Dane.

Which dog is known as the wolf killer?

The Karakachan dog: history and traits

The Karakachan dog is a Bulgarian livestock guardian breed, developed over centuries to protect flocks from predators including wolves. Its name translates loosely to “wolf killer” in local folklore, though the term is not an official breed designation. The Karakachan is large — typically 80–100 lbs — but not among the top five largest breeds by height or weight.

How the name “wolf killer” originated

According to historical accounts, the breed’s fearlessness and powerful bite made it effective at driving off and sometimes killing wolves. No modern registry uses the label officially.

Other breeds with similar reputations

The Kangal (Turkish shepherd dog) and the Caucasian Shepherd Dog are also known for wolf deterrence. Both are larger than the Karakachan — the Kangal averages 90–140 lbs, while the Caucasian Shepherd can reach 170 lbs — but neither holds record size in either height or weight.

What is the heaviest dog ever recorded?

Aicama Zorba: the legendary Mastiff

In 1989, Aicama Zorba of La-Susa — an English Mastiff — was officially weighed at 343 pounds (156 kg) by Guinness World Records. The Mental Floss (editorial site covering history and records) describes Zorba as both the heaviest and longest dog ever recorded. No living dog has officially surpassed Zorba’s verified weight.

Other heavy contenders

Several modern giant breeds, including English Mastiffs and Saint Bernards, often reach 200–250 lbs. The American Kennel Club (breed standard authority) notes that Mastiffs have the highest average weight of any breed. However, claims of 350+ lb dogs circulate on social media but lack official verification.

Weight versus height: which is more impressive

Zorba’s 343 lbs is roughly double the weight of a typical adult male lion. In contrast, Zeus’s 44 inches of height is about the same as a medium-sized pony. The trade-off: giant breeds that carry extreme weight face shorter lifespans and more joint problems, as PetPlace (pet-care resource) explains.

“Zeus is so tall that he can easily rest his head on top of a table or kitchen counter.”

Guinness World Records (official record-keeper)

“The Irish Wolfhound is the tallest breed of dog recognized by the AKC.”

American Kennel Club (purebred breed authority)

“The heaviest dog ever recorded was Aicama Zorba of La-Susa, an English Mastiff who weighed 343 pounds.”

USA Today (national news outlet)

For anyone searching for the biggest dog in the world, the answer is never one number. If you’re a potential owner looking at giant breeds, the trade-off between height and weight matters for your home, vet budget, and daily routine. The clearest takeaway: Great Danes dominate the height records, Mastiffs hold the weight crown, and Irish Wolfhounds win on breed average — but no single dog combines both extremes. For record chasers, the next verified contender will need to step onto an official scale or stand under a Guinness measure.

Frequently asked questions