Dog calorie calculator

How many calories a day a dog of a given weight needs, using the resting energy formula vets actually use — and showing the arithmetic rather than hiding it.

Where the number comes from

Energy needs do not scale in a straight line with body weight. A 40 kg dog is twice the weight of a 20 kg dog but needs nowhere near twice the food, because metabolic rate scales to roughly the three-quarter power of body mass. The standard veterinary form is:

RER = 70 × (body weight in kg) ^ 0.75

RER is the resting energy requirement — what the dog burns doing nothing. Real dogs do something, so RER is multiplied by a life-stage factor to give the maintenance energy requirement, the figure you feed to. The multipliers in the dropdown above are the conventional ones: 1.6 for a neutered adult, 1.8 intact, 2.0 for a growing puppy past four months, 3.0 below that, and 1.0 when a dog is meant to be losing weight.

What this figure does not know

Two dogs of identical weight can differ in real requirement by about 20% in either direction. Breed, coat, ambient temperature, thyroid function, how much of the body is muscle rather than fat, and how much the dog genuinely moves all shift it. Neutering reduces requirement by a step that surprises most owners, which is why it has its own multiplier rather than a footnote.

So the honest use of this number is as a starting ration. Feed it for a month, weigh the dog on the same scale at the same time of day, and let the trend correct the estimate. The scale is the measurement; the formula is only the opening guess.

Turning calories into cups

Calories are the unit that transfers between foods; cups are not. If you want the portion in cups, the food portion calculator does the second step using the kcal/cup figure printed on your bag.

Sources: Resting energy formula and life-stage multipliers: WSAVA Global Nutrition Guidelines