Cat Calorie Calculator
How much should your cat actually eat? Enter their weight and life stage for a daily calorie target with wet and dry food portion estimates - using the standard veterinary energy formula.
How we calculate it
We use the standard veterinary formula: Resting Energy Requirement (RER) = 70 × (weight in kg)0.75, multiplied by a life-stage factor - 1.2 for a neutered adult, 2.0-2.5 for kittens, 0.8 for weight loss, up to 2.4 for nursing queens. The result is your cat’s daily maintenance calories to stay at a healthy weight.
Portions vary a lot by brand - wet food averages about 95 kcal/100 g and dry about 375 kcal/100 g, so always check your label. Sharing from your plate? Check what cats can safely eat first, and see where your cat is in life with the cat age calculator. A free lifelong care plan keeps vaccines and check-ups on schedule too.
This tool gives general estimates only and is not veterinary advice. Weigh your cat monthly - if they need to slim down, cats must lose weight slowly to avoid liver problems, so step down gradually and involve your vet.
What this works out
A daily calorie figure for a cat, from weight and life stage, calculated in your browser with nothing transmitted anywhere. It gives you a number to compare against what the food you own actually provides.
It is a starting estimate. It does not know your cat, and a number produced from two inputs cannot carry the weight of a feeding decision on its own.
Why cats are harder to estimate than dogs
Cats occupy a much narrower weight range than dogs, so a small absolute error is a large proportional one. A hundred gram change means something quite different in a four kilogram animal than in a thirty kilogram one, which is why we are cautious about precision here and why you should be too.
Cats also tend to be fed in ways that resist counting: grazing across a day, more than one person topping up a bowl, and in multi cat households, an unknown split between animals. If you cannot say with confidence how much a specific cat is eating, the calculator’s output is describing a cat you may not have.
What a number cannot tell you
Body condition is assessed by hand, not by arithmetic, and it is assessed properly by someone trained to do it. Your vet does this at routine appointments and will talk you through what they are feeling if you ask.
We do not publish a self assessment chart for this. Owners scoring their own animals reliably drift toward the reassuring end, and a chart would give that drift an air of authority it has not earned.
The changes that are a phone call, not a calculation
Weight loss in a cat that has not had its food changed is one of the more important things an owner can notice, and it is a reason to phone your vet rather than to recalculate. The same is true of a marked increase in appetite or thirst, or a cat that stops eating.
We publish no feeding amounts for cats that are unwell, no therapeutic diets and no weight management protocols. Those are veterinary decisions and we are not veterinarians.
No brands, no commission
This tool names no product and earns nothing from your choice of food. It only cares about the calorie figure printed on whatever you already own.
