Tosa Inu

Breed overview

The Tosa, also known as the Japanese Mastiff, is a dog breed of Japanese origin that is considered rare. It was originally bred in Tosa, Shikoku (present-day Kōchi), as a fighting dog and the only dog legally allowed in Japanese dog fighting. Ownership is restricted in some countries as a dangerous breed.

• Breed classification: Japanese dogBreed reference breed group.
• Breed type: dog breedBreed reference breed kind.
• Country of origin: JapanBreed reference country of origin.

Breed facts

• The breed started with the native Shikoku-Inu (an indigenous dog weighing about 25 kilograms (55 pounds) and standing about 55 centimetres high).
• The aim was to breed a larger, more powerful dog specifically for dog fighting competitions in Japan.
• The heyday of Tosa breeding was between 1924 and 1933, when it was said that there were more than 5,000 Tosa breeders in Japan.
• The Tosa, also known as the Japanese Mastiff, is a dog breed of Japanese origin that is considered rare.
• Ownership is restricted in some countries as a dangerous breed.

Size and appearance

The Tosa vary considerably in size, with the Japanese-bred dogs tending to be about half the size of those bred outside the country. The Japanese breed generally weighs between 80 and 135 lb, while non-Japanese breeders have focused on dogs that weigh from 60 to 90 kg and stand 62 to 82 cm at the withers. The coat is characterized by its short and smooth appearance and is often red, brindle, or fawn, but occasionally it can be a dull black. Maintenance of the coat is usually minimal. Dogs can occasionally tip the scale at 200 lb. In Japan, they are considered the equivalent of sumo wrestlers and are even depicted in wrestling accoutrements.

• Height reference: 55 cm or moreBreed reference height. female, minimum.
• Height reference: 60 cm or moreBreed reference height. male, minimum.

• Coat length: short
• Coat texture: smooth

Personality and behavior

Care planning: record what your dog enjoys, how they greet visitors, and how they respond to new places. Add notes after walks and training so you can see their habits over time. Where this profile includes behavior research, use the same named measures when comparing your shortlist.

Exercise and activities

In South Korea, it is one of the main dog meat breeds, along with Nureongi dogs.

Training and enrichment

Care planning: choose one everyday skill to practice and keep a record of each session. Note the cue, the reward your dog enjoys and what went well. Rotate familiar games and new activities, and use your notes to choose the next small step.

Coat and grooming

Care planning: use the coat details above to discuss a grooming routine with your groomer. Record brushing sessions, baths and appointments in the app. Add the tools you use and your preferred schedule so the whole household can follow the same routine.

• Coat length: short
• Coat texture: smooth

Health and lifespan

Care planning: keep your dog's veterinary records, health-check dates and agreed care plan together. Add reminders for appointments and record changes you want to discuss at the next visit. Use the linked breed organizations and original references to explore their current health resources.

Living with this breed

Care planning: compare this profile's adult dimensions, coat care and available activity information with your household's routine. Make a shortlist, plan who will handle daily care and save the questions you want to ask a breed club, rescue or breeder.

Compare breeds

Compare supported adult height and weight ranges, matching research measures and sourced coat and care categories.

Breed history

This breed originated in the second half of the 19th century. The breed started with the native Shikoku-Inu (an indigenous dog weighing about 25 kilograms (55 pounds) and standing about 55 centimetres high). These dogs were crossed with European dog breeds, such as the Old English Bulldog in 1872, the English Mastiff in 1874, the Saint Bernard and German Pointer in 1876, the Great Dane in 1924, and the Bull Terrier. The aim was to breed a larger, more powerful dog specifically for dog fighting competitions in Japan. The heyday of Tosa breeding was between 1924 and 1933, when it was said that there were more than 5,000 Tosa breeders in Japan.

Clubs and further reading

• Tosa (dog breed) - article and references

Sources

1. Wikidata structured breed dataWikimedia contributors Retrieved 2026-10-14.License: CC0 1.0. Wikidata contributors (CC0).
2. National C-BARQ breed and all-breed means from USA.PLOS ONE / Figshare Retrieved 2026-10-14.License: CC BY 4.0. Bohland, Kyle R.; Lilly, Meghan Leanne; Herron, Meghan E.; Arruda, Andréia G.; O’Quin, Jeanette M. (2023). National C-BARQ breed and all-breed means from USA.. PLOS ONE. Dataset. https://doi.org/10.1371/journal.pone.0289356.s003 CC BY 4.0. Selected rows and field names adapted; values unchanged.
3. File:BUKADAI 2.jpgWikimedia Commons Retrieved 2026-10-14.License: CC BY-SA 3.0. BUKADAI 2.jpg - BUKADAI..JPG : Ludivine HOUDAS derivative work: Caronna ( talk ). CC BY-SA 3.0. Source: https://commons.wikimedia.org/wiki/File:BUKADAI_2.jpg. License: https://creativecommons.org/licenses/by-sa/3.0.
4. Tosa (dog breed) - WikipediaWikipedia contributors Retrieved 2026-10-14.License: CC BY-SA 4.0. Adapted excerpts from Wikipedia contributors, Tosa (dog breed), revision 1379653349. CC BY-SA 4.0. Formatting, citations and selection changed. Source history: https://en.wikipedia.org/w/index.php?title=Tosa_%28dog_breed%29&action=history
5. Palipaws everyday care planningPalipaws Retrieved 2026-10-14.License: Palipaws original factual summaries. Palipaws. Original care-planning text, separate from breed measurements and licensed article summaries.