Mastiff: healthy weight & calories
A healthy adult Mastiff usually weighs 54 to 100 kg (119 to 220.5 lb). That is a wide range because frame size varies a lot even within one breed, so how they feel under your hands matters more than the number alone.
Estimated for a Mastiff at 77 kg, a healthy weight in the middle of the breed range. Resting energy is 70 × weight0.75 kcal; the multiplier below scales it up for how much they move and whether they are desexed.
| Activity | Desexed | Entire |
|---|---|---|
| Mostly restsa few short potty walks | 2,183 kcal | 2,547 kcal |
| Short daily walks20 to 30 minutes total | 2,547 kcal | 2,911 kcal |
| Active most days45 to 60 minutes, some play | 2,911 kcal | 3,275 kcal |
| Very activeruns, hikes or dog sport | 3,275 kcal | 3,639 kcal |
Puppies get roughly twice their resting energy while growing, about 3,639 kcal a day at this weight, but puppy needs change every few weeks so this is a starting point, not a fixed number. Seniors typically need about 10% less than an adult at the same activity level.
Extra weight makes breathing harder for flat-faced breeds, and obesity is a major risk factor for airway problems. Keep walks cool, short and frequent rather than long, and avoid exercise in the heat.
Studies of dogs a similar size to a Mastiff found overweight dogs had a shorter median life span than lean ones, by 0.3 to 0.6 years (Salt et al. 2019). That is an association from observational data, not a promise, but it is one of the largest studies of its kind.
This page gives a breed-level estimate. For portions in grams, a calorie target adjusted for your dog's own age, activity and desexed status, and a 7-day activity plan, take the free 60-second check.
Check Mastiff free →How much should a Mastiff weigh?
A healthy adult Mastiff typically weighs 54 to 100 kg (119 to 220.5 lb). Frame size varies a lot within a breed, so body condition (can you feel the ribs?) matters more than the number on the scale.
How many calories does a Mastiff need a day?
A desexed adult Mastiff at a healthy weight typically needs roughly 2,547 kcal a day with short daily walks, more if they are very active or not desexed, less if they mostly rest. Use the calculator below for a number tailored to your dog.
Similar breeds: Boerboel, Saint Bernard, Neapolitan Mastiff
Also see: the dog calorie calculator · is my dog overweight? · all breeds
This is an estimate, not a diagnosis. Talk to your vet before changing your dog's diet or exercise. How we work this out