Enter your dog's weight, life stage or goal, and the calories printed on the food label. The calculator gives a daily calorie estimate and turns it into grams, and cups if you want them, for the food you actually feed, puppies included.
The starting point is the resting energy requirement, or RER: the calories a dog's body needs in a day just to keep running while lying still, before any walking or play. The formula is RER = 70 x body weight in kg raised to the power 0.75, from the 2021 AAHA Nutrition and Weight Management Guidelines. You don't need to work it out yourself; the calculator does it.
RER is then multiplied by a factor for your dog's life stage or goal. "1.6 x RER" means 1.6 times the resting figure. Where AAHA gives a range for a life stage, the calculator uses a single value from inside it. These are the values it uses:
A 20 kg neutered adult dog has an RER of about 662 kcal. At 1.6 x RER that is about 1,059 kcal a day. On a dry food with 3,600 kcal/kg, that works out to about 294 g a day.
A food with a different calorie density gives a different amount in grams for the same dog, which is why the calculator asks for the number on your label rather than assuming one.
The daily amount comes from dividing daily calories by the food's calorie density, meaning how many calories are in a kilogram or a cup of it. US labels carry a Calorie Content statement in kcal/kg and often kcal per cup; EU and UK labels usually give kcal/kg or kcal/100g. The label guide shows where to find these numbers.
For weight loss, the AAHA guidelines base the calculation on the dog's ideal weight, not its current weight, and the Pet Nutrition Alliance calculator does the same. Enter the target weight your vet gave you. If you leave it blank, the calculator uses current weight, and the result will be higher than your vet's plan would give.
Take a 40 kg dog with a 32 kg target. Using the weight-loss factor on the target weight gives about 942 kcal a day. The same factor on its current 40 kg would give about 1,113.
The result is a starting point for a healthy dog, not a diagnosis. Ask your vet before relying on it if your dog is pregnant or nursing, very overweight or underweight, diabetic, has kidney or heart disease, or is recovering from illness. Weigh your dog and check its body condition every two to four weeks, and adjust the amount gradually. Treats and chews count toward the daily total.
It depends on your dog's weight and life stage. A 20 kg neutered adult dog needs about 1,059 kcal a day. The calculator works out an estimate for any weight.
Puppies under 4 months use 3.0 x RER, while puppies over 4 months use 2.0 x RER. For a 5 kg puppy, that is about 702 kcal a day under 4 months and 468 kcal over 4 months. Needs change quickly during growth, so re-weigh and recalculate regularly.
Divide daily calories by the calorie density on the label, using kcal/kg for grams or kcal per cup for cups. For the 20 kg neutered adult dog eating 1,059 kcal a day, food with 3,600 kcal/kg works out to about 294 g a day. The calculator does this for you, in grams and, if you want them, cups.
Following the AAHA 2021 guidelines, the calculator applies the weight-loss factor to the target weight. For a 40 kg dog with a 32 kg target, that gives about 942 kcal a day. Agree the target weight with your vet.
Yes, pet food labels use kilocalories (kcal), which are the same unit as the Calories on human food labels. The calculator works in kcal throughout.