How many calories does a neutered adult Spanish Mastiff need?

At 170 lb, the verified feeding table lists 2914 kcal per day for a Spanish Mastiff (resting energy 1821 kcal times a factor of 1.6).

How many calories does an intact adult Spanish Mastiff need?

At 170 lb, the verified feeding table lists 3278 kcal per day for a Spanish Mastiff (resting energy 1821 kcal times a factor of 1.8).

How many calories does a Spanish Mastiff puppy under 4 months need?

At 170 lb, the verified feeding table lists 5464 kcal per day for a Spanish Mastiff (resting energy 1821 kcal times a factor of 3).

How many calories does the weight-loss row list for a Spanish Mastiff?

At 170 lb, the verified feeding table lists 1821 kcal per day for a Spanish Mastiff (resting energy 1821 kcal times a factor of 1).

Feeding calculator

How much to feed a Spanish Mastiff

A 170 lb Spanish Mastiff is the starting weight on this calculator, taken from the verified adult range (140–200 lb).

Last reviewed November 1, 2026.

Spanish Mastiff dog — Photo: Canarian · CC BY-SA 3.0 · Wikimedia Commons

Daily portion

Dog food calculator: 2623 kcal; 7.49 cups · 899 g · 2 meals
Merck chart, Adult, neutered: 2915 kcal; Resting energy 1822 kcal × 1.6, before the calculator's activity and size adjustment.

Lifespan10–12 years

Weight140–200 lb

SizeGiant

GroupFoundation Stock Service

Resting energy at that weight is about 1822 kcal per day. The Merck neutered-adult factor of 1.6 puts maintenance near 2915 kcal before activity is added. The dog food calculator on this page uses that same resting-energy formula, then applies the activity and size adjustments from the main dog food calculator.

Reading the portions

Compared with other single-size giant breeds, that neutered-adult portion is 726 kcal higher than the 2189 kcal for an average giant breed at 116 lb.

Portions are a starting estimate. Spanish Mastiff individuals can vary by body condition, neuter status, and how much they work. Adjust the bowl from what you see on the ribs, not from the table alone.

Feeding table from the verified weight chart

RER=70*kg^0.75; MER=RER*factor. Starting estimate only; individuals vary up to 50%; adjust by body condition

Spanish Mastiff adults maintenance energy

Swipe sideways to read every column.

Weight	RER	Adult, neutered	Adult, intact	Puppy under 4 months	Puppy 4 months and older	Weight loss
140 lb (63.5 kg)	1575 kcal	2519 kcal	2834 kcal	4724 kcal	3149 kcal	1575 kcal
155 lb (70.3 kg)	1699 kcal	2719 kcal	3059 kcal	5098 kcal	3399 kcal	1699 kcal
170 lb (77.1 kg)Current weight	1821 kcal	2914 kcal	3278 kcal	5464 kcal	3643 kcal	1821 kcal
185 lb (83.9 kg)	1941 kcal	3105 kcal	3493 kcal	5822 kcal	3881 kcal	1941 kcal
200 lb (90.7 kg)	2057 kcal	3292 kcal	3703 kcal	6172 kcal	4115 kcal	2057 kcal