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Enter your cat's weight in kilograms, choose life stage and activity level, and enter the calorie density from your food labels (dry food about 370 kcal per 100 g, wet food about 100 kcal per 100 g). The calculator first works out resting energy requirement from the veterinary RER formula, then applies life stage and activity factors to give daily calories, and converts those calories into dry food grams and wet food grams per day. These are estimates, not veterinary advice: adjust to body condition and your vet's guidance.
The veterinary starting point is resting energy requirement, RER = 70 × weight in kg to the power 0.75. For a 4 kg cat, 4 to the power 0.75 is 2.83, so RER is about 198 kcal per day. Daily calories then multiply RER by a life stage factor and an activity factor: kittens use 2.5 because they are growing, adults use 1.2, and seniors use 1.0, while low activity uses 0.9, moderate uses 1.0 and high uses 1.2. A 4 kg adult cat with moderate activity therefore needs about 238 kcal per day, which is about 64 g of dry food at 370 kcal per 100 g, or about 238 g of wet food at 100 kcal per 100 g. Use your cat ideal weight, not current weight, if your vet has set a target weight.
Weigh your cat on a scale and enter the weight in kg, choose the life stage and activity level that match your cat today, and enter the kcal per 100 g from your own food labels. Read daily calories first, then the dry and wet food grams. Split the daily portion into 2 to 3 meals, use a kitchen scale instead of a cup, because a cup of kibble varies a lot from one scoop to the next, and reweigh your cat after a few weeks and run the calculator again if weight has changed. Treats should stay under about 10 percent of daily calories; subtract treat calories before working out food portions.
Most adult indoor cats need about 200 to 260 kcal a day, depending on weight, age and activity. A 3 kg adult needs about 192 kcal, a 4 kg adult about 238 kcal, a 5 kg adult about 281 kcal and a 6 kg adult about 322 kcal at the 1.2 adult factor. Kittens need far more per kilogram because they are growing, and are usually fed 3 to 4 meals a day, while seniors need fewer calories but more protein to preserve muscle. Neutered cats need roughly 20 to 30 percent fewer calories than intact cats, because neutering lowers metabolic rate, which is why many neutered cats gain weight on pre-neuter portions.
Dry food typically contains 3500 to 4200 kcal per kg, while wet food contains far fewer calories but 70 to 80 percent water, which supports hydration and kidney health, especially in senior cats. Both can be nutritionally complete if they meet recognised standards. Many vets recommend a combination: split daily calories between wet and dry food by calories first, then convert each share to grams using its own label, rather than splitting by volume. Adding wet food on top of a full dry ration, without reducing the dry food, is one of the most common causes of gradual weight gain in cats.
A 4 kg adult cat with moderate activity: RER = 70 × 4 to the power 0.75 = about 198 kcal. Daily calories = 198 × 1.2 × 1.0 = about 238 kcal per day. Dry food = 238 / 370 × 100 = about 64 g per day. Wet food = 238 / 100 × 100 = about 238 g per day. Half from each type would be about 32 g dry plus 119 g wet. If your food label differs, enter its kcal per 100 g and the grams change automatically.
These are starting estimates, not professional veterinary advice. Cats with medical conditions such as diabetes, kidney disease or thyroid problems, pregnant or nursing queens, and highly active outdoor cats need individual guidance from a vet. If your cat is overweight, feed to ideal weight and aim for slow loss, about 0.5 to 1 percent of body weight per week, since rapid calorie cuts in cats can trigger serious liver problems. Monitor body condition weekly during any transition and adjust portions by about 10 percent at a time.
An average 4 kg indoor adult cat needs roughly 200 to 250 kcal per day, about 55 to 70 g of dry food or 200 to 250 g of wet food. Enter your cat weight, life stage and activity above for your own figure, then check your brand calorie content.
Most adult indoor cats need about 200 to 260 kcal a day. A 10 lb (4.5 kg) spayed indoor cat needs approximately 200 to 250 kcal per day, while active outdoor cats need 20 to 40 percent more.
Divide daily calories by the kcal per 100 g on your dry food bag and multiply by 100. A 4 kg adult needing 238 kcal eats about 64 g per day at 370 kcal per 100 g. Always measure with a kitchen scale, not a scoop.
Divide daily calories by the kcal per 100 g on your wet food label and multiply by 100. A 4 kg adult needing 238 kcal eats about 238 g per day at 100 kcal per 100 g, roughly two to three standard cans depending on can size.
Yes. Neutering lowers metabolic rate by roughly 20 to 30 percent, so neutered cats need less food than intact cats of the same weight. This calculator uses a lower adult factor for the typical neutered indoor cat; ask your vet if your cat is intact and very active.
Kittens under 4 months need about 4 meals a day, kittens 4 to 6 months need 3 meals a day, and cats over 6 months can move to 2 to 3 meals a day. Kittens need about 2.5 times resting energy requirement for healthy growth.
Both can be nutritionally complete. Wet food provides hydration that supports urinary and kidney health, while dry food is more calorie dense and convenient. Many veterinary nutritionists recommend a combination of both, split by calories.
Cats may act hungry from habit, boredom or food palatability rather than true hunger. If weight and body condition are healthy, resist overfeeding, try several small meals a day, and rule out medical causes such as hyperthyroidism or diabetes with a vet visit.