Cat Calorie Calculator
How many calories a cat needs depends on its weight and its state — neutered, intact, prone to weight gain, or a growing kitten. The estimate below uses the same resting-energy formula vets use, scaled by a factor for that state.
Daily calories
261 kcal
per day — for a 10 lb cat.
How many calories does a cat need?
Vets start from the resting energy requirement — the calories a cat burns at rest — then multiply by a factor for its state. The resting figure is 70 × (body weight in kg) raised to the power 0.75; the factor is 1.2 for a neutered adult, 1.4 if intact, 1 for a cat prone to weight gain, and 2.5 for a growing kitten.
Treat the number as a starting point, not a prescription: Merck notes an individual cat can differ by up to 30% from another cat of the same weight. Weigh your cat every few weeks and adjust the portion if it is gaining or losing.
Common questions
How many calories does my cat need a day?
Start from resting needs: 70 × (body weight in kg) raised to 0.75, then multiply by a factor for your cat's state. The Merck Veterinary Manual publishes 1.2 for a neutered adult, 1.4 for an intact one, 1 for a cat prone to weight gain and 2.5 for a kitten.
Why does neutering change the number?
A neutered cat burns less. Merck publishes 1.2 × resting needs for a neutered adult against 1.4 for an intact one — the same cat, fed the same way, gains weight after neutering unless the amount comes down.
Do other sources give the same answer?
Close, but not identical. The WSAVA Global Nutrition Committee publishes a table built on a different formula, covering adult cats from 4 to 7 kg, and across that whole span this calculator lands inside its published range. Below 4 kg the two methods separate, because they use different exponents; above 7 kg the WSAVA table stops, so there is no published range left to land inside. Treat any figure as a starting point.
Is this number exact for my cat?
No. Merck states that an individual animal can differ by up to 30% either way. Activity, age, climate and health all move the figure. Use it to set a starting amount, then adjust on what the scale and your veterinarian say.
How do I turn calories into food?
Look for the kcal per cup or per can on the label — every pet food sold in the United States must declare it. Divide the daily calories by that figure to get the amount. Treats count toward the same total.
This is a starting estimate. An individual cat’s real needs can run 30% higher or lower, and a weight-loss plan should be set with a veterinarian, not guessed. It does not replace professional advice.
Verified on . Based on Nutritional Requirements of Small Animals — energy requirements of the dog and cat (Merck Veterinary Manual, “Energy” section, accessed 2026-07-23). See the method.