My pet

How much should my cat eat?

Calories per day with the formula vets use, then the ounces or grams of YOUR cat’s food, read from its label.

Not a cat? Pick your pet

Weight (lb)

age (years)

Spayed or neutered?

How active?

Calories in its food (from the label)

Look for “metabolizable energy” on the bag or can.

Pregnant or nursing

Food amount

Always ask your vet: this site helps you understand, it doesn’t replace a checkup.

How it’s calculated

First the resting energy requirement: 70 × weight in kg^0.75. Then a factor for life stage and activity, from the Pet Nutrition Alliance table: adult spayed or neutered dog 1.6, intact dog 1.8, adult spayed or neutered cat 1.2, intact cat 1.4, growing puppies and kittens 2–3. Finally the grams: calories per day divided by the calories per gram of your pet’s food.

The same source says a pet can differ by as much as 50% from the estimate: it’s a starting point. Weigh your pet again in 2–4 weeks and adjust with your vet. For pregnancy, nursing or illness there’s no calculation here: ask your vet.

Sources

Pet Nutrition Alliance, “Calculating Calories Based on Pet Needs” (checked on October 6, 2026)