How big does a Mastiff get?

Adult Mastiffs typically stand about 70-76 cm tall and weigh 54-91 kg, making them one of the largest dog breeds. Because of their size, it's important to make sure you have enough space before bringing one home.

Is a Mastiff suitable for first-time owners?

Mastiffs are generally considered a breed for experienced owners rather than beginners. Their large size and strength make it best for them to go to owners who already have experience training big dogs.

What is the Mastiff's lifespan?

Mastiffs typically live around 6 to 10 years. Giant breeds tend to have shorter lifespans than smaller dogs, so consistent health care is especially important.

Are Mastiffs okay being left alone a lot?

Mastiffs are deeply devoted to their families and prefer spending time close to them. A household where they're regularly left alone for long periods isn't a great fit for this breed's temperament.

What should I know about feeding a Mastiff?

It's recommended to feed a high-quality food formulated for giant breeds. Splitting meals into 2-3 smaller portions a day, rather than one large meal, is also advised to help prevent bloat.

Mastiff

The Mastiff is one of the world's oldest giant dog breeds, with images appearing on reliefs dating back to before the common era. Despite their commanding size — standing about 70 to 76 cm tall and weighing between 54 and 91 kg — Mastiffs are known for their calm temperament and deep devotion to their families. Their imposing presence makes them natural watchdogs, yet their gentle nature also suits them to family life. Because of their massive size, they require an experienced owner with adequate space, making this a breed best suited to advanced keepers. With a lifespan of around 6 to 10 years, prospective owners should be prepared for a long-term commitment.

View Mastiff encyclopedia →

Find Mastiff breeders(0)

Limited Time Offer

0% commission on your first sales!Register by September 30, 2026 and your first 2 sales are commission-free!

Breeder Wanted!

List on BreederDirect and sell directly to customers nationwide!

Free registrationNo monthly feesCommission on sales only

4 Trust Pillars from BreederDirect

All puppy listings include full disclosure from verified Breeder. BreederDirect enforces legally-mandated standards for safe, transparent direct purchases.

MicrochipRequired
Vaccinated
Health Exam
Pedigree Certificate

※ Microchip implantation is mandatory for breeders under Japan's Animal Protection Law (effective June 2022).

Secure transaction guarantee

Dogs & cats only

Every BreederDirect transaction is covered by our transaction guarantee. If you cannot receive your pet, you will be fully refunded. A health guarantee also covers you after handover.

Learn about transaction safety →

All breeds Toy Poodle7 Chihuahua Long Coat Chihuahua Tiny Poodle Pomeranian Miniature Dachshund Shiba Inu Teacup Poodle French Bulldog Mameshiba Miniature Schnauzer Bichon Frise2

Browse all 232 breeds

—

Sort by

Verified breeders wanted for Dogs

Breeders are signing up now ahead of launch. Subscribe to be notified when new listings go live.

Find breeders Browse the Dogs encyclopedia

Getting alerts is free with a member account. When new listings match your saved search, we'll notify you by email and in-app.

Browse other categories

Cats Marine Fish Coral Tropical Fish Goldfish Medaka Reptiles & Amphibians Small Pets Birds Insects Exotic Invertebrates

Verified breeders (preview)

刘

刘宇婷 Breeder

岐阜県

宿

宿院利浩 Breeder

大阪府

阿

阿比留健太 Breeder

福岡県

中村美美 Breeder

鹿児島県 / 7 listings

渡部康則 Breeder

京都府

塚崎睦予 Breeder

奈良県

Are you raising dogs?

Apply as a breeder

Mastiff key facts

Care level: Advanced
Lifespan: 6-10 years
Size: Height approx. 70-76cm / Weight approx. 54-91kg
Diet: High-quality giant-breed dog food. Feed 2-3 times daily to reduce bloat risk.
Temperament: Calm and deeply affectionate toward its owner. Also capable as a guardian.
Exercise: 30-60 min of leisurely walks daily. Avoid intense exercise while growing.
Coat Care: Short, easy-care coat. Brush 1-2 times weekly.
Origin: United Kingdom
Notes: Giant size demands adequate space and budget. Watch for hip dysplasia and gastric torsion.

TraitsAdvancedGiantWatchdogMastiff

About Mastiff

The Mastiff is an ancient giant breed known for its massive build (70-76cm, 54-91kg), calm temperament, and deep loyalty. Best suited to experienced owners; lifespan is around 6-10 years.

7 things to know before welcoming a Mastiff

1Needs Plenty of Space
As a giant breed standing 70-76 cm tall and weighing 54-91 kg, Mastiffs need ample space both indoors and outdoors. A house with a yard suits them far better than a small apartment.
2Best for Experienced Owners
Mastiffs are considered a breed for experienced dog owners. Given their large size and strength, it's best for them to go to owners who already have experience raising and training big dogs.
3Gentle but Very Strong
Despite their calm temperament, Mastiffs weigh 54-91 kg and can exert tremendous force when they want to. Patient, consistent training and socialization from puppyhood are essential.
4Mind Their Diet
Choose a high-quality food formulated for giant breeds to meet their nutritional needs. Feeding them 2-3 smaller meals a day rather than one large meal is also recommended to help prevent bloat.
5Short Coat, Some Care Needed
Their short coat is relatively easy to maintain, though they do shed during seasonal changes. Regular care of facial wrinkles and drool is also important to keep them clean and comfortable.
6Deeply Devoted Companions
Mastiffs form deep bonds with their families and value time spent together. Try to avoid leaving them alone for long stretches so they can truly feel like part of the household.
7Lifespan of 6-10 Years
Mastiffs typically live 6 to 10 years, which is on the shorter side even among giant breeds. Prospective owners should be prepared to commit to consistent health care throughout their life.

Frequently asked questions about Mastiff

Q.How big does a Mastiff get?: A.Adult Mastiffs typically stand about 70-76 cm tall and weigh 54-91 kg, making them one of the largest dog breeds. Because of their size, it's important to make sure you have enough space before bringing one home.
Q.Is a Mastiff suitable for first-time owners?: A.Mastiffs are generally considered a breed for experienced owners rather than beginners. Their large size and strength make it best for them to go to owners who already have experience training big dogs.
Q.What is the Mastiff's lifespan?: A.Mastiffs typically live around 6 to 10 years. Giant breeds tend to have shorter lifespans than smaller dogs, so consistent health care is especially important.
Q.Are Mastiffs okay being left alone a lot?: A.Mastiffs are deeply devoted to their families and prefer spending time close to them. A household where they're regularly left alone for long periods isn't a great fit for this breed's temperament.
Q.What should I know about feeding a Mastiff?: A.It's recommended to feed a high-quality food formulated for giant breeds. Splitting meals into 2-3 smaller portions a day, rather than one large meal, is also advised to help prevent bloat.