Breeds / Giant
Tosa puppies
Quiet, composed and deeply loyal to their own family, the Tosa is a large Japanese mastiff type that is watchful with strangers and intolerant of other dogs.
The facts
- Size class Giant
- Country of origin Japan
- Adult weight 45.4 to 90.7 kg
- Adult weight in pounds 100 to 200 lb
- Adult height 55 to 60 cm
- Energy level Moderate
- Grooming Low
- Coat type Short double and smooth
- Shedding Low
- Typical lifespan 10 to 12 years
- Good with children Fine with supervision
- Good with other dogs Not recommended
About the Tosa
The Tosa was created in the Kochi region of Japan in the nineteenth century by crossing the native Shikoku dog with imported Mastiff, Great Dane, Bulldog and Pointer stock, producing a large mastiff type for the Japanese fighting ring, where silence and composure were prized above noise. The coat is short, dense and smooth over a very heavy frame. At home the breed is typically quiet, watchful and slow to fuss, but this is a serious guardian with the lowest possible rating for tolerance of other animals.
Ownership is restricted or banned outright in a number of countries, so checking local law comes before anything else. Grooming is simple: a weekly going over of the short coat, regular nail trims and routine ear checks. Exercise is modest for the size, daily walks and calm play rather than hard running. The breed needs an experienced handler, thorough early socialisation and a secure garden, and they do not suit a multi pet home. However placid they seem in the house, keep up the supervision.
The law in your country
This breed or type is restricted in some places. Check the current rules where you live before you commit to a puppy.
Australia
The Japanese Tosa is on the list of pure breeds that cannot be imported into Australia under Department of Home Affairs legislation. The Department of Agriculture says the import of mixed breed dogs, including mixes involving these breeds, is not restricted. Source.
United Kingdom
The Japanese Tosa is one of the banned types of dog in the UK, alongside the Pit Bull Terrier, Dogo Argentino, Fila Brasileiro and XL Bully. It is against the law to sell, give away, abandon or breed from one, and a dog can only be kept with a valid Certificate of Exemption, which requires the dog to be neutered, microchipped, kept on a lead and muzzled in public, and kept somewhere secure. Whether a dog counts as a banned type depends on what they look like rather than their breed or name. From 1 November 2026 a child under 12 must not be left in close contact with a banned dog in a private place, such as a home or garden, without adult supervision. Source.
New Zealand
The Japanese Tosa is listed as a type of dog in Schedule 4 of the Dog Control Act 1996. A dog that belongs wholly or mainly to that type cannot be imported, and the local council must classify it as menacing, which means it must be muzzled in any public place and the council can require it to be neutered. Source.
What to expect at eight weeks
At eight weeks a Tosa puppy is sleeping around 18 to 20 hours a day, is not house trained, and cannot hold on for more than an hour or two at a stretch. A giant breed puppy at eight weeks is already heavy and will keep growing for up to two years. Controlled growth matters more here than in any other size class, so a large breed specific puppy food and no overfeeding. Expect moderate energy, in short bursts separated by long naps. Grooming is straightforward, but start handling the coat, feet and ears in week one anyway so it is never a fight later. The socialisation window is open and closing: everything they meet calmly now, from vacuum cleaners to men in hats, is easier for the rest of their life.
Health worth knowing about
Conditions this breed is reported to be predisposed to. Predisposed does not mean inevitable, it means ask about it.
- Hip and elbow dysplasia, screened by hip and elbow evaluation of breeding stock
- Bloat and gastric torsion, a surgical emergency in deep chested dogs
- Entropion and ectropion of the eyelids, diagnosed on clinical eye examination
- Hypothyroidism, detected by a thyroid blood panel
Your Tosa puppy's first six months
- Vaccination schedule, dated for your country.
- Worming and parasite schedule.
- Feeding calculator. Set expected adult size to Giant for a Tosa.
- Adult size predictor, to check growth against the 45.4 to 90.7 kg adult range.
- Puppy names and the first week checklist.
Kit sizes: crate 48 inch (48 x 30 x 32 in, 122 x 76 x 81 cm) for an adult of up to 90.7 kg, the largest size in the chart, which tops out at 49.9 kg, so measure the dog before you buy; chew toys made for large breeds. Worked out the same way as the crate size calculator. PetMD bases a crate on the dog's own measurements, not weight or breed alone, so measure once the puppy is home.
Buying guides for this
Other giant breeds
More on the Tosa
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Not veterinary advice. Breed information is general. Your own dog, and your own vet, always win.
Sources
- akc.org for adult weight and height, life expectancy, energy, grooming, shedding and the temperament ratings, coat type and health notes
- fci.be for country of origin
- gov.uk for the legal status notes
- Health notes from Tosa breed information at https://www.akc.org/dog-breeds/tosa/. Discuss any of these with your own vet.
Photo: Томасина, CC BY-SA 4.0, via Wikimedia Commons, cropped. All photographers are listed on the photo credits page.