Dog calorie calculator

How the estimate is worked out

It starts with resting energy requirement, the calories a dog burns doing nothing at all. That is calculated as 70 multiplied by their weight in kilograms to the power of 0.75. The curve matters: energy needs do not rise in a straight line with weight, which is why a 40kg dog does not need twice what a 20kg dog needs.

That figure is then multiplied by an activity factor, from 1.2 for a dog who mostly sits about to 1.8 for one getting substantial daily exercise. The result is a maintenance estimate: roughly what it takes to keep your dog at the weight they are now.

What it does not account for

Quite a lot, which is why it is a starting point rather than an answer. Neutered dogs typically need around 20 to 30 percent fewer calories than intact ones. Breed changes things, and so does coat, climate and whether your dog spends winter outdoors. Any ongoing health condition can change the picture entirely.

Treats count too, and they are where most overfeeding quietly happens. As a rule of thumb, treats should be no more than about a tenth of daily intake, with the rest coming from balanced food. If you are training heavily, take the treat calories out of meals rather than adding them on top.

Grams and cost per day

Every pack lists its energy content, usually as kcal per kilogram or per 100g. Divide your dog’s daily calories by that and you have grams per day, which is often quite different from the feeding guide on the back of the bag. Guides are written for an average dog, and many dogs need less.

The cost per day uses one standard price from a named UK retailer for each food, checked on the date shown, and ignores offers and subscriptions. Wet foods are mostly water, so they always cost more per day than dry. We do not rank or score the foods: all of them are sold as complete, and the right one is the one your dog does well on.

Use body condition, not just the number

The scales tell you less than your hands do. You should be able to feel your dog’s ribs easily under a thin layer of fat without pressing, see a waist from above, and see the belly tuck up from the side. If you cannot feel ribs without pushing, they are carrying too much regardless of what any calculator says.

Weigh monthly, adjust in small steps of around ten percent, and give any change a few weeks before judging it. If your dog needs to lose weight, do it slowly and with your vet involved, because rapid loss causes its own problems.