What Is the Strongest Dog Breed? The Measured Answer, by Each Measure

Almost every ranking of the strongest dog breeds is one writer’s opinion dressed up with a bite-force number nobody measured. This page uses published competition results instead, breed by breed, and says “no published figure” wherever the results do not exist.

The short answer

“Strongest” depends on which of four measures you mean. By absolute weight moved, the heaviest single-dog figure in the Unified Pulling Federation’s published results is a Boerboel’s, 22,039 lb on rails. Pound for pound, bully breeds lead, headed by the American Pit Bull Terrier. By bite force, no breed has ever been measured. By sustained draft, northern sled breeds.^{[1, 5, 9, 18]}

Those four answers are not variations on one question. They are four different contests, judged on four different pieces of evidence, and three of them have a different winner from the first. Below is each one with the actual source attached.

1. Absolute weight moved

Leader: Boerboel

The heaviest single-dog figure in the Unified Pulling Federation’s published results is 22,039 lb on rails, recorded on 9 May 2026 for two Boerboels, at body weights of 164 lb and 186 lb.^{[1, 3, 4]} We downloaded all 1,485 event sheets in that federation’s archive back to 2014 and parsed roughly 10,900 result rows; nothing in it is heavier.^[2]

2. Pound-for-pound ratio

Leader: bully breeds, headed by the American Pit Bull Terrier

On the same results sheet as that 22,039 lb figure, a 38 lb American Pit Bull Terrier moved 18,332 lb, about 482 times its own body weight, and a 26 lb dog of the same breed matched the multiple.^[1] Same day, same cart, same rails. The best Boerboel ratio on that sheet was 176 times body weight.

3. Bite force

Leader: unknown, and unknowable from current data

The most-cited figure in the world is the Kangal at 743 PSI, and it is an estimate rather than a measurement of that breed: no published study has ever measured a Kangal’s bite.^[21] The largest in vivo dog bite-force dataset used 20 mixed-breed dogs of 5 to 40 kg and reported newtons, not PSI, and was never built to rank breeds.^{[18, 19]}

4. Sustained draft over distance

Leader: northern sled breeds

Weight pull is a 16-foot sprint against a load, not distance work.^[7] The only dog-pulling record Guinness currently lists is a 210-dog sled team moving 145,302 lb at Whitehorse, Yukon on 22 October 2000, which works out to roughly 692 lb per dog and is not a single-dog figure at all.^[9]

Why “strongest” has no single answer

Before any table is worth reading, three things have to be said plainly, because every one of them limits what a table like this can prove.

1. There is no standardized cross-breed strength test

Nobody runs dogs of different breeds through one calibrated protocol and publishes the results. Weight pull alone is split across at least fifteen separate sanctioning organizations in North America, Europe and Australia, each with its own rulebook, and there is no unified cross-federation records list anywhere.^[11] Even inside one rulebook the numbers are not one scale: the UKC credits an advanced dog with up to 65 times its body weight on rails but only 25 times on snow, which is a property of the surface, not of the dog.^[7] So any ranking presented as the answer is smuggling in a choice of test that its author never states.

2. Weight pull is the only published cross-breed contest, and it is self-selecting

Competitive weight pull is the one strength contest that is judged, open to all breeds, and published with the dog’s body weight and the pulling surface attached. That makes it the best evidence available. It also means a breed that does not enter cannot appear in the results, and absence from a results sheet is not a measurement of weakness.

The scale of that problem is easy to show. The American Pulling Alliance’s public dog database holds 6,188 competing dogs, and roughly two thirds of them are American Pit Bull Terriers and American Bulldogs.^[5] It contains one Newfoundland, two Tibetan Mastiffs, and no Kangal at all. The breed that tops nearly every “strongest dog” list on the internet has never, as far as any published results sheet shows, pulled a cart in a sanctioned competition.

3. Nearly every breed bite-force figure online is an estimate

The PSI tables that anchor most strongest-dog articles are not measurements of the breeds they name. They are estimates, extrapolations from other species, or numbers copied from an earlier list, and the pages that publish them cite no study.^[21] The actual literature goes the other way: the largest in vivo dataset measured 20 mixed-breed dogs chosen for varied skull shape, not breed, and reported newtons of force.^[18] The standard methodological review reports newtons and publishes no breed table.^[19] PSI is pressure, force divided by contact area, and no one has published the tooth-contact area a breed PSI figure would need.

There is a fourth point worth adding, because it cuts against the popular framing generally. A 2025 study of 117 canid skulls across 40 breeds found that breeds grouped by their historic jobs overlap almost completely in skull shape, so breeding for a task has not produced the specialized anatomy people assume.^[20] A heavy breed is powerful because it is heavy and well muscled, not because it carries equipment other breeds lack.

Our interest in this question

We breed and sell Boerboels. The two dogs holding the heaviest absolute figure in the table below, 22,039 lb on rails, are littermates sired by our stud Peterbuilt Hakeem. That is a direct commercial interest in one of the four answers on this page, and you should weight our Boerboel claims accordingly.

So here is how to check us rather than trust us. The result sheet is a public PDF published by the sanctioning body, and each dog has its own profile PDF on the same site: the 9 May 2026 event sheet, Sun Wukong’s profile and Wednesday’s profile.^{[1, 3, 4]} Every other figure in the table has a public source in the same way.

Two rules we have held ourselves to on this page, and which you can hold us to. We never write “the Boerboel is the strongest dog breed” in our own voice anywhere, because that is not a claim a results sheet supports; the permitted form is that the heaviest single-dog figure in the Unified Pulling Federation’s published results is a Boerboel’s. And where the breed loses, we say so in its own section rather than a footnote, which is three of the four measures.

Sixteen breeds, side by side

One summary row per breed. Every pull figure below was read this session off a sanctioning body’s own published results: the Unified Pulling Federation’s event sheets, or the American Pulling Alliance’s per-dog career records, which we swept for all 582 competing dogs carrying these breed labels and 4,218 individual result rows.^{[1, 2, 5, 6]}

Where a figure does not exist, the cell says “no published figure.” Nothing here is estimated, interpolated, or carried over from another article. Body weights are the male ranges from the breeds’ own registries.^{[12, 13, 14, 15, 16, 17]}

Sixteen powerful dog breeds compared on typical male weight, best-documented single-dog weight pull with surface and sanctioning body, best-documented pound-for-pound ratio, bite-force measurement status, and original working purpose
Breed	Typical male weight	Best documented pull	Best pound-for-pound	Bite force	Original working purpose
Boerboel	150-200 lb	22,039 lb, rails (UPF)	176x body weight, rails (UPF)	Never measured	South African farm and homestead guardian
English Mastiff	160-230 lb	7,592 lb, rails (APA)	58x body weight, rails (APA)	Never measured	English estate guardian and holding dog
Cane Corso	No weight in the standard (25-27.5 in tall)	10,425 lb, rails (APA)	85x body weight, rails (APA)	Never measured	Italian farm guardian and boar catch dog
Rottweiler	95-135 lb	6,425 lb, rails (APA)	92x body weight, rails (APA)	Never measured	Cattle drover and butcher's cart dog
American Pit Bull Terrier	35-60 lb	18,332 lb, rails (UPF)	482x body weight, rails (UPF)	Never measured	19th-century fighting and farm catch dog
American Staffordshire Terrier	55-70 lb	11,304 lb, rails (APA)	159x body weight, rails (APA)	Never measured	Bull-and-terrier stock bred to a show standard
Presa Canario	100-125 lb	19,834 lb, rails (UPF)	177x body weight, rails (UPF)	Never measured	Canary Islands cattle dog and property guardian
Greater Swiss Mountain Dog	115-140 lb	14,445 lb, rails (APA)	144x body weight, rails (APA)	Never measured	Swiss draft and drover dog, an actual cart breed
Alaskan Malamute	85 lb	12,979 lb, rails (APA)	183x body weight, rails (APA)	Never measured	Arctic freighting sled dog
Newfoundland	130-150 lb	6,632 lb, rails (APA)One Newfoundland in the entire APA database	50x body weight, rails (APA)	Never measured	Water rescue and draft haulage for fishermen
Saint Bernard	140-180 lb	7,125 lb, rails (APA)	48x body weight, rails (APA)	Never measured	Alpine hospice search and rescue
Kangal	110-145 lb	No published figureNo Kangal appears anywhere in APA's 6,188-dog database or in UPF's results	No published figure	Never measured (743 PSI is an estimate)	Anatolian livestock guardian against wolves
Great Dane	140-175 lb	11,716 lb, rails (APA)	83x body weight, rails (APA)	Never measured	German boar-hunting dog, later an estate guardian
Dogo Argentino	80-100 lb	10,784 lb, rails (APA)	154x body weight, rails (APA)	Never measured	Argentine big-game catch dog
Tibetan Mastiff	90-150 lb	1,620 lb, rails (APA)Two Tibetan Mastiffs on record, one of which ever pulled; treat as no data	13x body weight, rails (APA)	Never measured	Himalayan flock and monastery guardian
German Shepherd	65-90 lb	7,122 lb, rails (APA)	113x body weight, rails (APA)	Never measured	German herding and tending dog, later police and military service

UPF figures come from that federation’s own event sheets and dog profiles;^{[1, 2, 3, 4]} APA figures come from the individual career records published for every dog in its database.^{[5, 6]} Every pull figure above was set on rails, which keeps the column internally comparable, but see the next section for why that still is not a clean ranking of breeds. Named dogs, event dates, completion times and the disputed record claims live on the full weight-pull records ledger, federation by federation.

How to read those numbers

A best-ever figure is the maximum of a sample, and the samples are wildly uneven. The American Pit Bull Terrier column rests on thousands of entries; the Tibetan Mastiff column rests on one dog at one event, and the Newfoundland column on one dog in the entire archive.^[5] A single-dog sample is not a breed result, and we have flagged the rows where that applies rather than letting them read like evidence.

Venue matters as much as breed. Rail carts are built to a rulebook but not to a single specification, and the ceiling differs from track to track. Several of the highest figures in the table were set at European rail events, where the numbers run systematically higher than at most North American ones. The honest reading is that a best-ever column partly ranks which tracks a breed’s best dogs happened to attend. That caveat applies to the Boerboel row exactly as much as to any other.

Absolute and ratio are different sports. A 38 lb dog moving 482 times its body weight and a 186 lb dog moving 22,039 lb are both remarkable, and neither result predicts the other.^[1] Heavier dogs win the absolute column almost by definition, because there is more animal to push against the ground; lighter dogs win the ratio column for the same reason in reverse. Any list that merges the two is answering a question it has not defined.

An empty cell is a finding, not a gap. The Kangal is the breed most often named the strongest dog in the world, and it has no published pull figure of any kind, in either federation archive.^{[2, 5]} That does not make it weak. It means the claim has never been tested, and everyone repeating it is repeating an opinion.

Where the Boerboel loses

We breed this one, so this section gets stated without hedging. Of the four measures on this page, the Boerboel wins one. Here are the other three, plus a fourth that people ask about.

Pound for pound: bully breeds win outright, by a wide margin

This is not close and it is not arguable. At the same event, on the same rails, on the same day as the 22,039 lb figure, a 38 lb American Pit Bull Terrier pulled 482 times its own body weight while the heaviest Boerboel pull on the sheet came to 134 times, and the best Boerboel ratio anywhere on it was 176 times.^[1] That is a gap of nearly three to one, measured in a single afternoon with no surface excuse available to either side. American Staffordshire Terriers and Dogo Argentinos sit far ahead of the Boerboel on this measure too.^[5]

Bite force: the breed cannot be ranked at all

No Boerboel bite force has ever been scientifically measured. Not once. That does not mean the breed places low on this axis, it means the breed has no place on this axis, and neither does any other breed in the table. Every PSI figure you have seen attached to a Boerboel is fabricated, and we take those numbers apart in detail on our Boerboel bite-force page.

Sustained draft over distance: northern breeds

Weight pull asks for 16 feet in under a minute.^[7] Freighting asks for a loaded sled for hours, day after day, in cold that would flatten a short-coated mastiff. That is the Alaskan Malamute’s and the sled breeds’ actual job description, and the only dog-pulling record Guinness recognizes is held by a 210-dog sled team.^[9] A Boerboel is not a distance draft animal and was never bred to be one.

Speed and agility: lighter breeds, and no one has measured it either

There is no published cross-breed sprint or agility test to point at, so we are not going to invent a ranking. What can be said plainly is that a 150 to 200 lb dog is not the animal anyone picks for speed or quickness, and the lighter breeds in this table beat the Boerboel on both. For the breed-scoped version of the strength question, including what kind of strength the build actually delivers, see how strong a Boerboel is.

One column out of four, with a public results sheet behind it and a disclosed commercial interest in front of it. That is the whole of the Boerboel claim on this page.

The bite-force column, and why it is empty

Sixteen rows, and the bite-force column reads “never measured” in every one. That is not an oversight in our research. It is the state of the published evidence, and it is the single biggest reason strongest-dog rankings are unreliable, because bite force is usually the number they are built on.

Here is what actually exists. The largest in vivo canine bite-force dataset measured 20 dogs weighing 5 to 40 kg, deliberately chosen for a spread of skull shapes rather than by breed, and reported forces in newtons.^[18] The standard methodological review of the field reports newtons as well and publishes no breed table.^[19] Neither was designed to compare breeds, and nothing since has done it.

What circulates instead is a chain of copied lists. The Kangal’s 743 PSI is the most-repeated figure in the genre, and the pages carrying it cite no study, no equipment and no sample size.^[21] The unit is wrong too: PSI is pressure, which is force divided by the contact area of the tooth, and that area has never been published for any breed, so a breed PSI figure cannot be calculated even in principle from the data that exists.^[19]

Boerboel PSI figures circulate as well, and they are invented in exactly the same way; we take that specific claim apart, with sources, on our Boerboel bite-force page.

What a normal dog can pull

For calibration against the five-figure numbers above: the UKC’s own titling standard asks a fit, conditioned competition dog for 3 times its body weight on a snow sled, 8 times on a wheeled cart and 10 times on rails, and that, not 22,039 lb, is the scale an ordinary well-conditioned pet dog works at.^{[7, 10]}

The full surface ladder, the caps that withdraw a dog once it reaches 65 times body weight on rails, and how the same dog can post a twentyfold difference between rails and snow are all covered on the full weight-pull records ledger, federation by federation. If you are considering trying the sport with your own dog, start there rather than here.

Strongest Dog Breed FAQ

What is the strongest dog breed?

There is no single answer, because strength is four different measures with four different winners. By absolute weight moved, the heaviest single-dog figure in the Unified Pulling Federation's published results is a Boerboel's, 22,039 lb on rails. Pound for pound, bully breeds lead, headed by the American Pit Bull Terrier at up to 482 times body weight. By bite force, no breed has a published measurement, so nobody can answer it. By sustained draft over distance, northern sled breeds.

Which dog has the strongest bite?

Nobody knows, and the numbers you have seen are not measurements. The most-cited figure is the Kangal at 743 PSI, an estimate that no published study of that breed supports. The largest in vivo dog bite-force study measured 20 mixed-breed dogs of 5 to 40 kg, reported its results in newtons rather than PSI, and was never designed to rank breeds. A breed PSI figure also cannot be calculated without a tooth-contact area that nobody has measured.

What dog is strongest pound for pound?

Bully breeds, led by the American Pit Bull Terrier. At a Unified Pulling Federation rail event on 9 May 2026, a 38 lb American Pit Bull Terrier moved 18,332 lb, about 482 times its own body weight, and a 26 lb dog of the same breed hit the same multiple. The best Boerboel ratio at that event was 176 times body weight. American Staffordshire Terriers and Dogo Argentinos also post very high multiples, at 159 and 154 times body weight in the American Pulling Alliance's archive.

Is a pit bull stronger than a mastiff?

On both measures anyone has published, yes. The heaviest documented American Pit Bull Terrier pull is 18,332 lb on rails, against 7,592 lb for the heaviest English Mastiff figure in the American Pulling Alliance's archive. Pound for pound it is not close, about 482 times body weight against about 58. The Mastiff is roughly three times heavier, so if by stronger you simply mean bigger and heavier, the Mastiff wins that and only that.

Is the Boerboel the strongest dog breed?

Not on three of the four measures on this page. The breed wins one column: the heaviest single-dog figure in the Unified Pulling Federation's published results is a Boerboel's, 22,039 lb on rails on 9 May 2026. Pound for pound, bully breeds beat it outright, at up to 482 times body weight against 176 for the best Boerboel figure at that same event. On bite force no Boerboel has ever been measured, so the breed cannot be ranked on that axis at all. On sustained draft over distance, northern sled breeds do the work.

How is dog strength actually measured?

Only one way, in competitive weight pull, where a harnessed dog draws a loaded cart 16 feet in 60 seconds or less in front of judges, and the result is published with the dog's body weight and the pulling surface. Nothing else about canine strength is measured to a published standard: there is no cross-breed grip test, no cross-breed draft test and no breed-level bite-force measurement. Weight-pull figures are also only comparable when the surfaces match, because a low-friction rail cart yields numbers several times higher than a snow sled.

What dog can pull the most weight?

The heaviest single-dog figure in any weight-pull federation’s published results is 22,039 lb on rails, recorded for two Boerboels at a Unified Pulling Federation event on 9 May 2026. Our dog weight-pull records page carries the full ledger, federation by federation, including the historical and disputed claims.

How much weight can a dog pull?

It depends far more on the surface than on the dog: the UKC’s own titling standard asks a competition dog for 3 times its body weight on a snow sled, 8 times on a wheeled cart and 10 times on rails. The surface ladder in full, along with the caps that withdraw a dog once it reaches 65 times body weight on rails, is on our dog weight-pull records page.

Sources & further reading

[1] Official results sheet, 'Spring Into Bully Max' weight pull, 5/9/26, Pittsburg PA, surface stated as Rails: the four heaviest rows are Boerboels at 22,039 lb (164 lb dog) and 22,039 lb (186 lb dog), a Boerboel at 21,336 lb, and Presa Canarios at 19,834 lb; the highest multiple of body weight on the sheet is 482.42x by a 38 lb American Pit Bull Terrier at 18,332 lb. Unified Pulling Federation (UPF). https://unifiedweightpullfederation.com/assets/files/events/events_6a5b6241a0346.pdf
[2] Published results archive, filterable by season from 2014 to 2026; we downloaded all 1,485 event sheets in it and parsed roughly 10,900 internally consistent result rows, and nothing we could read out of them is heavier than 22,039 lb. Unified Pulling Federation (UPF). https://unifiedweightpullfederation.com/results/
[3] Official dog profile, Sun Wukong (Boerboel, weight class Unlimited 120 lb+): 22,039 lb on Rails, 5/9/26, Pittsburg PA, at a body weight of 164 lb. Unified Pulling Federation (UPF). https://unifiedweightpullfederation.com/pdfs/profiles/dog_pdf_6a5d2610969e6.pdf
[4] Official dog profile, Wednesday (Boerboel, weight class Unlimited 120 lb+): 22,039 lb on Rails, 5/9/26, Pittsburg PA, at a body weight of 186 lb. Unified Pulling Federation (UPF). https://unifiedweightpullfederation.com/pdfs/profiles/dog_pdf_6a5d26ea399c0.pdf
[5] Dog profile database, 6,188 competing dogs with breed labels, each linking to that dog's full career results with surface, body weight, weight pulled and multiple of body weight; the source for every APA figure in the table below, and for the finding that the database contains no Kangal and no Anatolian Shepherd. American Pulling Alliance (APA). http://www.weightpull.com/profile/profile2.asp
[6] Published event results, 2003 to 2026, organized by season (the events behind the individual career records we swept). American Pulling Alliance (APA). http://www.weightpull.com/results/home2.asp
[7] Official Weight Pull Rulebook: a qualifying pull is 16 feet in 60 seconds or less; title weight requirements are 3x body weight on snow, 8x on wheels and 10x on rails; a dog is automatically withdrawn at 15x on snow, 20-25x on wheels and 45x on rails in the lower division, and at 25x, 28-35x and 65x respectively in the higher one. United Kennel Club. https://www.ukcdogs.com/docs/rulebooks/weight-pull-rulebook.pdf
[8] IWPA Championship record tables by class and surface (wheels on natural surface, wheels on artificial surface, snow); IWPA sets records only at its Championships and sanctions no rails. International Weight Pull Association (IWPA). http://www.iwpa.net/IWPA_Championships.html
[9] Heaviest weight pulled by a dog sled team: 65,910 kg (145,302 lb) by 210 dogs, Whitehorse, Yukon, 22 October 2000. This is the only dog-pulling title Guinness currently lists, and it is a team category. Guinness World Records. https://www.guinnessworldrecords.com/world-records/76753-heaviest-weight-pulled-by-a-dog-sled-team
[10] Competitive canine weight pull: qualifying multiples of 3x on sleds, 8x on carts and 10x on rails, and the owner-reported figure of 3,900 lb, about 90.7 times body weight, by a 43 lb American Staffordshire Terrier. Whole Dog Journal. https://www.whole-dog-journal.com/training/tricks_games_sports/competitive-canine-weight-pull/
[11] Weight pulling: at least fifteen separate sanctioning organizations across North America, Europe and Australia, each with its own rules, and no unified cross-federation records list. Wikipedia. https://en.wikipedia.org/wiki/Weight_pulling
[12] Breed pages and official standards (male height and weight ranges quoted in the comparison table for the AKC-recognized breeds). American Kennel Club. https://www.akc.org/dog-breeds/
[13] Official Standard of the Cane Corso: height 25 to 27.5 inches for dogs, weight stated only as 'Proportionate to height', so the standard sets no weight range at all. American Kennel Club. https://images.akc.org/pdf/breeds/standards/CaneCorso.pdf
[14] Official Standard of the Boerboel: size is defined by height, and the AKC breed page gives 150 to 200 pounds. American Kennel Club. https://images.akc.org/pdf/breeds/standards/Boerboel.pdf
[15] Breed standard, American Pit Bull Terrier: desirable weight for a mature male in good condition is 35 to 60 pounds. United Kennel Club. https://www.ukcdogs.com/american-pit-bull-terrier
[16] Breed standard, Perro de Presa Canario: minimum weight for a mature male 100 pounds, maximum 125 pounds. United Kennel Club. https://www.ukcdogs.com/perro-de-presa-canario
[17] Breed standard, Kangal Dog: typical weight for a male in good condition is 110 to 145 pounds. United Kennel Club. https://www.ukcdogs.com/kangal-dog
[18] Calibration of estimated biting forces in domestic canids (Ellis, Thomason, Kebreab & France, 2008): in vivo bite forces measured in 20 dogs of 5 to 40 kg selected for varied skull shape, reported in newtons; the study was not breed-specific and was not designed to rank breeds. Journal of Anatomy / PubMed Central (PMC2423399). https://pmc.ncbi.nlm.nih.gov/articles/PMC2423399/
[19] Bite Forces and Their Measurement in Dogs and Cats (Kim, Arzi et al., 2018): the authoritative review of canine bite-force methodology, which reports force in newtons and publishes no breed table. Frontiers in Veterinary Science 5:76. https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2018.00076/full
[20] Dog skull shape challenges assumptions of performance specialization from selective breeding (Hebdon et al., 2025): 117 canid skulls across 40 breeds and 18 wild subspecies; breeds grouped by historic function overlap almost completely in skull morphology. Science Advances 11(5):eadq9590. https://www.science.org/doi/10.1126/sciadv.adq9590
[21] What is the strongest dog breed? Top 10 contenders (cited as a representative example of the unsourced popular ranking this page is correcting, not as evidence: it opens with the Kangal at 743 PSI and cites no study for any figure). ManyPets. https://manypets.com/us/blog/what-is-the-strongest-dog-breed/

Last reviewed August 2026. Weight-pull figures are federation-specific and surface-specific and are not directly comparable across surfaces or sanctioning bodies. Breed weights are registry standard ranges for males and vary by line and individual. No cell in the comparison table is an estimate: where no published figure exists, the cell says so.