Mastiff Energy Needs
Informational, not a feeding prescription. These figures are general guidance, not veterinary advice. Calorie and portion ranges are transparently computed from the published NRC energy formula (RER = 70 × kg0.75) applied to the breed’s weight range — an estimate, not a per-dog prescription. Individual needs vary with metabolism, body condition, neuter status and activity. Confirm your dog’s plan with your veterinarian.
A Mastiff's resting energy requirement (RER — the calories it burns at rest) works out to about 1403-2285 kcal a day, computed straight from the published formula RER = 70 × (body weight in kg)^0.75 across its adult weight range. Its maintenance energy requirement (MER) is that RER multiplied by a life-stage factor.
For this breed that gives roughly 2244-4113 kcal/day for a typical neutered-to-intact adult, with puppies, working dogs and seniors landing higher or lower. These are informational estimates from the published energy math, not a prescription — your dog's real needs vary, so confirm with your veterinarian.
| Measure | Estimated calories |
|---|---|
| Resting (RER) | 1403-2285 kcal/day |
| Neutered adult | 2244–3656 kcal/day |
| Intact adult | 2525–4113 kcal/day |
| Active / working | 2806–11425 kcal/day |
| Puppy (growth) | 2806–6855 kcal/day |
| Senior | 1683–3199 kcal/day |
Full feeding guide → · How much to feed →
Computed from the published NRC RER/MER formula for the breed’s 120-230 lb weight; breed facts from its AKC breed page, verified June 2026. How we compile this.