How much should I feed an adult Bullmastiff?

A healthy adult Bullmastiff (about 100–130 lb) needs roughly 1,900–2,400 calories a day — about 5½ to 7 cups of dry food, split into two meals. The exact cups depend on your food's kcal per cup (check the bag); see the adult row matching your dog's weight.

How many times a day should a Bullmastiff eat?

Two measured meals a day for adults — not one large bowl. AKC's Bullmastiff feeding guidance flags bloat risk and recommends two daily meals so the dog doesn't have to digest too much food at once. Growing puppies eat several smaller meals across the day.

How much should I feed a Bullmastiff puppy?

A Bullmastiff puppy under 4 months is fed about 3× its resting energy needs across 3–4 small meals a day; from 4 months it steps down toward 2× across 3 meals. AKC notes most Bullmastiff breeders use a large-breed puppy formula (or adult food) to keep growth slow and steady. Find your puppy's current weight in the puppy rows of the chart above for an estimated daily amount, and confirm with your vet.

Can my Bullmastiff exercise right after eating?

No — AKC's Bullmastiff guidance specifically discourages exercise immediately before and after eating because of bloat risk. Give the dog a settled rest window around meals; save walks and play for well clear of mealtime.

When should a Bullmastiff switch from puppy to adult food?

Around 18 months — much later than smaller breeds. Giant breeds like the Bullmastiff are still filling out their frame past the one-year mark, and switching too early can rush growth in a way that affects long-term joint health. Your vet can confirm timing based on your dog's actual growth.

How do I know if my Bullmastiff is overweight?

A general body-condition check: you should be able to feel the ribs without pressing through fat, with a clear waist tuck behind the ribcage. Bullmastiffs are massive dogs, so even modest excess weight adds significant load on hips and joints — easier to prevent than to reverse.

When will my Bullmastiff stop growing?

Per AKC's Puppy Growth Chart, giant breeds like the Bullmastiff reach about 80% of their adult size by 12 months and full adult size by about 18 months. Bullmastiffs typically hit their adult height first, then continue to fill out in chest and muscle for several more months.

What is the average adult weight of a Bullmastiff?

AKC's Bullmastiff Breed Standard sets adult weight at 110-130 pounds for males and 100-120 pounds for females.

Bullmastiff Feeding Chart: How Much to Feed by Age & Weight

A healthy adult Bullmastiff (100–130 lb) needs roughly 1,900–2,400 calories a day — about 5½ to 7 cups of dry food. Split it into two meals rather than one large bowl, and skip heavy exercise right before and after eating: AKC's Bullmastiff feeding guidance specifically warns about bloat risk and pairs two daily meals with an exercise-around-meals caution.

Growing Bullmastiff puppies need more per pound, fed across several small meals, and as a giant breed they shouldn't be moved onto adult food too early — around 18 months is typical to give the frame time to develop. AKC notes most Bullmastiff breeders use a large-breed puppy food (or adult food) specifically to keep growth slow and steady. The chart below gives sourced starting points by weight; the calculator tailors them to your dog.

Healthy adult Bullmastiff with fawn coat and dark mask standing beside a food bowl

Last updated 2026-06-03 · Every number links to its source.

💪 Bullmastiff Adult Size & Growth

Bullmastiff adult size and growth chart — male and female weight and shoulder-height ranges plus when this breed is fully grown

See raw data

Sex	Weight	Shoulder height
Male	110-130 pounds	25-27 inches
Female	100-120 pounds	24-26 inches

Fully grown by 18 months (Giant breeds typically reach adult height first, then fill out in chest and muscle).

Per AKC's Puppy Growth Chart, Giant breeds reach about 50% of their adult weight by 6 months, 65% by 9 months, 80% by 12 months, 90% by 15 months, and 100% by 18 months.

How much should my Bullmastiff eat? ↓Can my Bullmastiff eat this food? →

Source: AKC Bullmastiff official breed standard; AKC When Do Dogs Stop Growing? — every number verified verbatim.

Daily Feeding Amounts by Weight & Age

Find your dog's current weight in the chart for an estimated daily amount. Calories come from the Merck Vet Manual energy formula; cups assume a typical ~350 kcal/cup dry food, so check your bag's label for its exact kcal/cup.

Bullmastiff feeding chart — daily food by weight and age

⬇ Save chart as image

See the exact numbers as a table

Puppy (under 4 months) — 4 meals/day

RER × 3.0 (Merck, high-growth window)

Weight	Daily calories	~ Cups/day	~ Grams/day
15 lb	885 kcal	2.5	253 g
30 lb	1488 kcal	4.3	425 g
45 lb	2017 kcal	5.8	576 g
60 lb	2502 kcal	7.1	715 g

Puppy (4 months to 18 months) — 3 meals/day

RER × 2.0 (Merck)

Weight	Daily calories	~ Cups/day	~ Grams/day
15 lb	590 kcal	1.7	169 g
30 lb	992 kcal	2.8	283 g
45 lb	1344 kcal	3.8	384 g
60 lb	1668 kcal	4.8	477 g

Adult — 2 meals/day

RER × 1.6 neutered (Merck; intact a little more, obesity-prone a little less)

Weight	Daily calories	~ Cups/day	~ Grams/day
100 lb	1958 kcal	5.6	559 g
110 lb	2103 kcal	6	601 g
120 lb	2244 kcal	6.4	641 g
130 lb	2383 kcal	6.8	681 g

These are healthy-dog starting points, not a strict rule — body condition and activity vary. Confirm your dog's target with your veterinarian. For your exact dog, use the calculator below.

Is my puppy a healthy weight for its age?

Rather than one “correct” weight, vets track puppies against evidence-based growth standards that run from 12 weeks to 2 years.

Those standards are grouped by a dog's adult body size (up to 40 kg), not by individual breed.

We don't publish a per-age “your puppy should weigh X” figure — that belongs on a vet's growth chart, weighed over time. What we give you instead is the daily caloriesfor your dog's actual weight today (the chart above and the calculator below), every number cited.

Adjust this plan for your own dog

The plan below is for a typical Bullmastiff. Change the details to match yours.

Breed

Age

Young puppies are usually counted in weeks. We use your dog's exact age — feeding frequency and calories follow different age guidelines, so we apply each separately.

Weight (lb)

What are you trying to figure out today?

This plan is general guidance for a healthy dog. If your dog has a health condition — or is a senior whose needs are changing with age — your veterinarian should be the final word.

The plan for a typical Bullmastiff

🐕 Here's the plan for your Bullmastiff

Healthy puppy (4 months+) · 4 months old · 65 lb

1771 cal/day · ~5.1 cups · 3 meals/day

🍽 HOW MUCH YOUR BULLMASTIFF PUPPY SHOULD EAT

Your little one is growing fast — and that takes fuel. About 1771 calories a day will keep your bullmastiff on a healthy track.

Here's what that looks like in your kitchen:

📏 ~ 506 grams on a kitchen scale

🥤 ~ 5.1 standard measuring cups (the 1-cup kind)

☕ ~ 2.5 large coffee mugs worth

Split into 3 meals a day:

≈ 590 calories per meal (~169 g / ~1.7 cup)

Why 3 meals?

Puppies have small stomachs and growing bodies that want food often. As your dog grows, you'll feed less often:

• 6 to 12 weeks: 4 meals a day
• 3 to 6 months: 3 meals a day ← your puppy now
• 6 to 12 months: 2 meals a day
• After age 1: 2 meals a day

Just look up your puppy's age in months and pick the row that matches.

📦 One quick thing:every brand has slightly different calories per cup. Your bag's label tells you exactly — look for “kcal per cup” and divide 1771 by that number for your real cup count.

💧 Water~65 oz/day▼

A good rule of thumb: a weaned puppy needs about ½ to 1 ounce of water per pound of body weight each day. The numbers below use the higher end as a safe target — most dogs settle in somewhere in this range.

For your 65-pound bullmastiff, that's:

💧 ~ 65 oz / ~ 1922 ml a day

🥤 ≈ 8.1 measuring cups

🍶 ≈ 4.1 standard 16-oz water bottles (Aquafina / Poland Spring size)

Keep the bowl filled with fresh water.

🍬 Treatsup to 177 cal/day▼

Treats are great for training and bonding — but they should be the bonus, not the main course.

The 90/10 rule keeps things balanced:

• 90% of daily calories from real dog food
• 10% from treats, chews, table scraps — anything extra

For your 65-pound bullmastiff at 1771 calories/day, that means up to 177 calories from treats.

💡 Don't forget the small stuff. That bite of cheese you sneak them, the piece of chicken from dinner, the dental chew before bed — it all counts toward the 10%. Adds up faster than most of us expect.

🛒 How to choose dog food▼

Walking into the pet store can be overwhelming. But you only need to check the back or side of the dog food bag for these things:

☐ The bag has an AAFCO Nutritional Adequacy Statement that mentions “growth”
Look for a full sentence on the back or side of the bag containing both “AAFCO” and “growth”. Typical wording is one of two formats:
- “[Brand] is formulated to meet the nutritional levels established by the AAFCO Dog Food Nutrient Profiles for growth.”
- “Animal feeding tests using AAFCO procedures substantiate that [Brand] provides complete and balanced nutrition for growth.”
For large-breed puppies (adults expected to exceed 70 lb), the statement should also mention large size dogs.
☐ “Calories per cup” is printed on the bag
Usually in the feeding guide section. You need this number to know exactly how much to scoop for your dog.

🚫 FOODS TO KEEP AWAY FROM YOUR BULLMASTIFF

Some everyday human foods are dangerous — even tiny amounts can cause serious harm. Keep these well out of reach:

Never feed: chocolate, xylitol (sugar-free gum / candy / some peanut butters), grapes, raisins, onions, garlic, macadamia nuts, alcohol, caffeine, avocado.

⚠️ Xylitolis a sweetener that's safe for humans but can be deadly to dogs. If your dog ingests anything containing xylitol, call your vet right away.

A few feeding habits to skip:

Free-feeding (leaving food out all day). It sounds convenient but makes portion control and weight monitoring much harder.
Switching food suddenly. Transition over 7-10 days — mix the new food with the old in growing proportions to avoid an upset stomach.
Switching to adult food too early. Puppy formulas are higher in protein than adult formulas — tuned for the demands of growth. When to actually switch? Small breeds (under 20 lb) at 8-12 months; medium breeds (20-50 lb) around 12 months; large breeds (50+ lb) at 12-15 months; giant breeds at 18-24 months.

📚 WHERE WE GOT ALL THIS

Every number and recommendation above comes from one of these sources. Tap any (▼) citation throughout the page to see the original wording. Full source documents are linked below.

MERCK — Merck Veterinary Manual ↗The Merck Veterinary Manual (published as MSD Veterinary Manual outside the U.S. and Canada) is a free, comprehensive veterinary reference used by veterinarians, students, and pet owners worldwide. Its nutrition chapters are authored by named board-certified veterinary nutritionists.
AAFCO — Association of American Feed Control Officials ↗AAFCO is a non-profit organization of U.S. state and federal feed-control officials that develops model regulations and nutrient profiles for pet food. Every dog food sold in the U.S. must meet AAFCO's standards to be marketed as 'complete and balanced'.
AKC — American Kennel Club ↗The AKC is the largest U.S. registry of purebred dogs and a widely-cited authority on general dog care, breed information, and owner education. Its Chief Veterinary Officer and expert advice column publish nutrition guidance for everyday dog owners.
FDA — U.S. Food and Drug Administration ↗The FDA is the U.S. federal agency that regulates food and drug safety, including pet food. Its Center for Veterinary Medicine publishes safety alerts about ingredients and household items toxic to pets.
PMC — PubMed Central (NIH) ↗PubMed Central is a free archive of peer-reviewed biomedical and life-sciences research curated by the U.S. National Library of Medicine (NIH). Papers cited here are open-access primary sources.

Last verified: 2026-05-23

❤️ A friendly reminder: this is general guidance, not a custom plan for your dog.

The plan above reflects what the Merck Veterinary Manual, AAFCO, AKC, and the FDA publish for dogs matching your Bullmastiff's breed, age, weight, and life stage. But every dog is different — habits, digestion, and individual quirks aren't in our data.

If something seems off, or you just want a second opinion, your vet is the right call. We've put together some talking points below to make that conversation easier ↓

🩺 QUESTIONS TO BRING TO YOUR VET

Save or print this list and bring it to your next visit.

❓ “What body condition score is my Bullmastiff at now, and what's the ideal?”
Why ask: The 1-9 body condition score is the standard vets use to tell if your dog is at a healthy weight.
❓ “Is my Bullmastiff puppy's growth rate on track?”
Why ask: Large breeds are sensitive to growing too fast. Your vet can compare current weight to the expected range for this age.
❓ “When should we transition from puppy to adult food?”
Why ask: For large breeds the transition can be later than 12 months — your vet can advise based on actual growth.
❓ “Are there breed-specific screenings or watches for Bullmastiffs at this age?”
Why ask: Bullmastiffs have known breed traits worth monitoring — your vet may suggest preventive screening based on age and lineage.

Bullmastiff feeding — common questions

How much should I feed an adult Bullmastiff?: A healthy adult Bullmastiff (about 100–130 lb) needs roughly 1,900–2,400 calories a day — about 5½ to 7 cups of dry food, split into two meals. The exact cups depend on your food's kcal per cup (check the bag); see the adult row matching your dog's weight.
How many times a day should a Bullmastiff eat?: Two measured meals a day for adults — not one large bowl. AKC's Bullmastiff feeding guidance flags bloat risk and recommends two daily meals so the dog doesn't have to digest too much food at once. Growing puppies eat several smaller meals across the day.
How much should I feed a Bullmastiff puppy?: A Bullmastiff puppy under 4 months is fed about 3× its resting energy needs across 3–4 small meals a day; from 4 months it steps down toward 2× across 3 meals. AKC notes most Bullmastiff breeders use a large-breed puppy formula (or adult food) to keep growth slow and steady. Find your puppy's current weight in the puppy rows of the chart above for an estimated daily amount, and confirm with your vet.
Can my Bullmastiff exercise right after eating?: No — AKC's Bullmastiff guidance specifically discourages exercise immediately before and after eating because of bloat risk. Give the dog a settled rest window around meals; save walks and play for well clear of mealtime.
When should a Bullmastiff switch from puppy to adult food?: Around 18 months — much later than smaller breeds. Giant breeds like the Bullmastiff are still filling out their frame past the one-year mark, and switching too early can rush growth in a way that affects long-term joint health. Your vet can confirm timing based on your dog's actual growth.
How do I know if my Bullmastiff is overweight?: A general body-condition check: you should be able to feel the ribs without pressing through fat, with a clear waist tuck behind the ribcage. Bullmastiffs are massive dogs, so even modest excess weight adds significant load on hips and joints — easier to prevent than to reverse.
When will my Bullmastiff stop growing?: Per AKC's Puppy Growth Chart, giant breeds like the Bullmastiff reach about 80% of their adult size by 12 months and full adult size by about 18 months. Bullmastiffs typically hit their adult height first, then continue to fill out in chest and muscle for several more months.
What is the average adult weight of a Bullmastiff?: AKC's Bullmastiff Breed Standard sets adult weight at 110-130 pounds for males and 100-120 pounds for females.

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