An English Mastiff male can weigh 230 lbs. That’s three of Buck, and Buck’s no small Lab. So if you’re thinking about a Mastador, the first thing I’d ask is whether your car, couch and budget are ready for a dog that might outweigh you.
The Mastador is a cross between a Mastiff and a Labrador Retriever. Most are big to giant dogs of about 100 to 180 lbs, with a gentle, loyal, often watchful temperament. I’d call it a calm family guardian with a Lab’s soft heart, as long as you’re ready for the size, the drool and a shorter lifespan than a Lab’s.
What is a Mastador?
A Mastador combines a Mastiff, usually the English Mastiff, with the Labrador Retriever. It’s a designer mix, not a recognized breed. Some breeders and rescues also use “Mastador” for Lab crosses with other mastiff-type breeds, such as the Bullmastiff or Cane Corso, so it’s worth asking exactly which mastiff is in the mix.
Here are the quick facts I’d want:
| Trait | What to expect |
|---|---|
| Parent breeds | Mastiff and Labrador Retriever |
| Height (inches) | About 25 to 30 |
| Weight (lbs) | About 100 to 180 |
| Lifespan (years) | About 8 to 12 |
| Coat | Short and dense |
| Colors | Fawn, apricot, brindle, black, yellow, chocolate |
| Energy | Low to moderate |
| Good with kids | Yes, with supervision because of size |
| Good for first-time owners | Possible, with a committed training plan |
These ranges are my estimates, built from the AKC figures for both parents. A giant parent and a large parent can produce a wide range in one litter.
Where the Mastiff Lab mix comes from
The Mastiff is an ancient guardian type. Large mastiff dogs guarded estates in Britain for centuries, and the modern English Mastiff was shaped there as a calm, dignified watchdog. The AKC Mastiff profile describes the breed as courageous, dignified and good-natured, which I think is a fair summary of a dog that guards mostly by being enormous.
The Labrador’s story is quite different. Its ancestors worked alongside fishermen in Newfoundland, retrieving nets and fish from cold water, and it was refined in Britain as a gun dog.
It’s famous for a friendly, people-loving temperament.
I’d guess the Mastador started as accidental crosses, then caught on during the designer-dog trend. Breeders who aim for it want a calmer, more trainable giant: Mastiff presence with a Lab’s easy manner.
Size and appearance
This is a very big dog. I can’t stress that enough. Most Mastadors are tall, heavy-boned and broad-chested, with a large head and loose lips. Some look like a giant Lab. Others look like a Mastiff with a slimmer face.
This is how the parents compare, using AKC figures:
| Dog | Height (inches) | Weight (lbs) | Lifespan (years) | My take |
|---|---|---|---|---|
| Labrador Retriever | 21.5 to 24.5 | 55 to 80 | 11 to 13 | Buck’s 78 lbs |
| Mastiff | 27.5 and up | 120 to 230 | 6 to 10 | A gentle giant |
| Mastador (estimate) | 25 to 30 | 100 to 180 | 8 to 12 | Plan for giant |
Giant dogs grow slowly, and most Mastadors keep filling out until about 2 or even 3 years old. Their growth plates close later than a Lab’s, which matters for exercise (more on that below).
A Mastador needs space. A house with a yard is a much easier fit than a small apartment, and I’d plan for an XXL crate, a giant orthopedic bed and a car with a ramp.
Colors and coat
Mastadors usually have a short, dense coat that’s easy to look after, and I’m grateful for that on a dog this size. Colors depend on the parents:
- Fawn or apricot with a black mask, from the Mastiff
- Brindle, also from the Mastiff
- Solid black, yellow or chocolate, from the Lab
- Small white patches on the chest or toes
The black mask on the face is a classic Mastiff feature and shows up in many Mastadors.
Image credit: daisythemastador / Instagram
Mastador temperament and personality
Most Mastadors are gentle, affectionate and calm at home. They’re couch dogs at heart. They’re usually patient with children and deeply loyal to their family. The Mastiff side often adds a quiet, watchful protectiveness.
This is how the parents compare:
| Trait | Labrador | Mastiff | The Mastador |
|---|---|---|---|
| Friendliness with strangers | Very high | Reserved | Friendly to watchful |
| Protectiveness | Low | High | Moderate to high |
| Energy (AKC score, 1 to 5) | 5 | 3 | 3 to 4 |
| Barking (AKC score, 1 to 5) | 3 | 1 | Low |
| Drooling (AKC score, 1 to 5) | 2 | 4 | Moderate to high |
Labs are famously not much use as guard dogs, but a Mastador often is a decent watchdog. It rarely barks without reason, and a deep bark from a 150 lb dog tends to end most conversations at the door. Good socialization keeps that protectiveness calm and sensible rather than suspicious.
Drool deserves an honest mention too. I won’t sugarcoat it. Mastiffs drool a lot, and Mastadors with loose jowls do the same, especially after drinking or eating. I’d keep a towel near the water bowl.
Mastadors love their people and don’t like long stretches alone. They’ll let you know. Separation anxiety can show up as chewing, howling or destroyed doors, and a giant dog can do a lot of damage quickly.
Training a Mastador
Training starts on day one, because manners matter more with every pound. A Mastador puppy jumping on you is cute. A 150 lb adult doing the same can put someone in the hospital.
Mastadors are smart and usually want to please, in my view, but the Mastiff side can be slow and stubborn. Some simply lie down when they’ve had enough, and you can’t drag a giant dog anywhere. Positive reinforcement works best: small treats, praise and short sessions of 5 to 10 minutes.
These are the skills I’d put first:
- Socialization from 8 weeks: calm adults, kids, friendly dogs, vet visits, traffic.
- Loose-leash walking with a well-fitted harness, long before the puppy outweighs you.
- “Off” and calm greetings with four paws on the floor.
- “Leave it” and trading games, to prevent resource guarding.
- Short alone-time practice in a crate.
- Settling on a mat while visitors are in the house.
From my experience with big retrievers, the dogs that are easiest to live with are the ones whose owners practiced leash manners when the dog was small enough to correct gently. With a Mastador, that window closes fast. A group puppy class is worth every penny.
Exercise needs
Mastadors need daily exercise, but they don’t need marathons. About 45 to 60 minutes a day for a healthy adult works for most, split into two or three walks plus some play.
| Age | Daily exercise | Good activities | Go easy on |
|---|---|---|---|
| Puppy (to 18 months) | Short sessions, several a day | Sniff walks, gentle play, training | Jogging, stairs, jumping, rough play |
| Adult (2 to 6 years) | 45 to 60 minutes | Walks, swimming, fetch on grass | Running on pavement, hot days |
| Senior (6+) | 20 to 40 minutes | Slow walks, gentle swims | Long hikes |
The puppy row matters most. Giant-breed puppies have soft, growing joints, so I wouldn’t jog with a Mastador, let it leap in and out of cars, or let it run stairs until your vet says its growth plates have closed.
Swimming is great exercise if your Mastador likes water. It works the muscles without pounding the joints. Buck still chases dock bumpers in freezing weather at 9, and many Lab mixes share that love of water.
Heat is a real risk for heavy dogs with loose jowls. On warm days, walk early or late, carry water and stop if your dog’s panting hard or lagging. Heatstroke needs a vet straight away.
Mastador health and lifespan
Most Mastadors live about 8 to 12 years. That’s the part I find hardest. The AKC lists 6 to 10 years for the Mastiff and 11 to 13 for the Lab, and size is the main reason for the gap. Giant dogs age faster.
These are the conditions I’d watch for:
| Condition | From which parent | Watch for | When to call the vet |
|---|---|---|---|
| Bloat (GDV) | Both, Mastiff especially | Swollen belly, retching with nothing coming up | Immediately |
| Hip and elbow dysplasia | Both | Limping, stiffness, bunny hopping | If it lasts more than a day or two |
| Cruciate ligament tears | Both | Sudden hind leg lameness | Same day |
| Heart disease | Mastiff | Tiring easily, coughing, fainting | Within a few days |
| Bone cancer | Mastiff | Lameness that doesn’t improve, swelling | Promptly |
| Progressive retinal atrophy | Both | Night blindness | At the next checkup |
Bloat is the one I’d learn about before the puppy comes home. Deep-chested giant breeds are among the most at risk of gastric dilatation-volvulus, where the stomach fills with gas and can twist. The American College of Veterinary Surgeons calls it a life-threatening emergency. A swollen belly with unproductive retching means get to an emergency vet now, day or night. Ask your vet whether a preventive gastropexy at spay or neuter time makes sense.
Joints take a beating in a dog this heavy. Buck developed mild elbow osteoarthritis at 8, and a daily joint supplement with glucosamine, chondroitin and omega-3s brought back his morning bounce within about three weeks. A dog twice his size needs its own plan, though, and I’m not a vet, so talk to yours before adding supplements.
Mastiffs can also carry cystinuria, an inherited condition that causes bladder stones, and some lines have eye problems such as PRA and entropion. Ask any breeder for hip and elbow results, a heart exam, an eye exam and relevant DNA tests on both parents.
Feeding a Mastador
Puppies need a large or giant-breed puppy formula. I wouldn’t compromise on that. These foods control calcium and calories so the puppy grows steadily, which protects developing hips and elbows. Keep a Mastador puppy lean, not chubby.
For adults, use the food label for your dog’s weight as a starting point, then adjust by body condition. What I’d keep in mind:
- Feed two or three smaller meals a day, never one huge one
- Wait about an hour after meals before exercise
- Raise the bowl only if your vet recommends it
- Count treats, which add up quickly
- Check the ribs and waist every couple of weeks
Labs often carry a gene variant linked to bigger appetites, and many Lab mixes inherit it. Around age six, Buck started gaining on the same portions, and a higher-protein, lower-calorie food split into three meals got him back to 78 lbs within four months. On a 150 lb frame, every extra pound is more strain on the joints.
Ask your vet before adding fish oil, glucosamine or probiotics.
Grooming
The short coat’s easy, but the size and drool add work. I’d budget the time. My grooming kit for a Mastador:
- A rubber curry brush (I’d pick a mitt for the face)
- A deshedding tool for spring and fall
- Face towels for drool and jowls
- Ear cleaner and cotton pads
- Heavy-duty nail clippers or a grinder
Brush once or twice a week, more during seasonal sheds. Wipe the face and jowl folds after meals. Trim nails every few weeks, which is far easier if you start in puppyhood. Bathing a giant dog is a project, so I’d bathe only when needed, and a self-serve dog wash with a raised tub saves your back.
Living with a giant dog
The size touches everything, and it isn’t just walks. Before committing, I’d check these honestly:
- A car that fits a 150 lb dog, plus a ramp
- Grippy floors, because giant dogs slip on smooth wood
- Room for an XXL crate and a big orthopedic bed
- A budget for giant-dog food, medication and boarding
- Someone home for much of the day
Medication and anesthesia are dosed by weight, so a routine dental or surgery costs more than it would for a Lab. I’d look at pet insurance before the puppy comes home.
Is a Mastador right for you?
Based on my research, the happiest Mastadors live with calm, patient owners who have space and don’t mind a little drool. My honest take:
A Mastador is a good fit if:
- You want a gentle, loyal family dog with a protective side
- Your home, yard and car have room for a giant dog
- Moderate daily walks suit you better than long runs
- You’ll train consistently from puppyhood
Skip it if:
- You live in a small apartment or a hot climate without air conditioning
- You can’t physically handle a very strong dog on a leash
- A spotless, drool-free house matters to you
- You’d struggle with a shorter lifespan
Adopting or buying a Mastador
I’d look at rescues first. There’s always a giant mix waiting. Mastiff rescues and Lab rescues both take in mixes, and giant dogs often end up in shelters when families underestimate the size. An adult dog also shows you its final size, energy and drool level. Many adopted adults are already house-trained, though any dog needs time to settle into a new home.
If you buy a puppy, look for a breeder who:
- Shows OFA or PennHIP hip and elbow results for both parents
- Shares heart and eye exam results
- Tests for cystinuria and PRA where relevant
- Lets you meet the mother and see where the puppies live
- Offers a contract that includes taking the dog back if needed
Skip anyone selling giant-mix puppies with no health results.
FAQ
How big does a Mastador get?
Most Mastadors grow to about 25 to 30 inches tall and 100 to 180 lbs. Males are usually larger, and Mastiff-leaning dogs can be heavier still. They keep filling out until about 2 to 3 years old.
Are Mastadors good family dogs?
Yes, Mastadors are usually gentle, patient and loyal family dogs that are good with children. Their size is the main concern, so supervise young kids and train polite manners early. They suit families with space and time for daily walks.
Are Mastadors good guard dogs?
Mastadors are often good watchdogs. The Mastiff side brings a calm protectiveness and a deep bark, while the Lab side keeps them friendly. Good socialization keeps that protectiveness sensible rather than suspicious.
How long do Mastadors live?
Mastadors usually live about 8 to 12 years. The AKC lists 6 to 10 years for the Mastiff and 11 to 13 for the Lab. A lean body, health-tested parents and knowing the signs of bloat all help.
Do Mastadors drool?
Many do. Mastiffs are heavy droolers, and Mastadors with loose jowls drool too, especially after drinking, eating or in warm weather. Lab-leaning dogs with tighter lips drool less.
My final word
A Mastador is a big commitment in every direction: more food, more drool, a bigger car and a shorter time together than with a Lab. But for the right family, it’s a calm, gentle giant that’ll lean against your legs and quietly keep an eye on the door. That’s a pretty good deal.
