Free tool
Cat food calculator
How much wet or dry food should your cat get? The calculator works out daily energy with the veterinary formula and converts it into grams of your food.
Daily portion
–g / day
An individual pet's needs can differ by as much as 30%. Weigh your cat every 2–4 weeks and adjust the portion by 10% if the weight goes up or down. Count treats in the daily total (no more than about 10% of calories).
How the calculator works
We calculate the resting energy requirement (RER): 70 × body weight in kg to the power of 0.75, then multiply it by a factor:
- kitten: 2.5 × RER,
- spayed or neutered adult: 1.2 × RER,
- intact adult: 1.4 × RER,
- inactive or prone to weight gain: 1.0 × RER,
- weight loss: 0.8 × RER for the target weight.
We divide the calories by the energy density of the food to get grams. Obesity is one of the most common problems in indoor cats, so it is better to start at the lower end and keep an eye on the scale.
Frequently asked questions
How much should I feed my cat a day?
A spayed or neutered adult cat weighing 4.5 kg (10 lb) needs about 260 kcal a day. That is about 270 g of wet food (95 kcal per 100 g) or about 70 g of dry food (370 kcal per 100 g). The calculator gives you a result for your own cat.
How much wet food should a cat eat?
Wet food usually has 70 to 130 kcal per 100 g, so portions are several times bigger than with dry food. A typical adult cat eats 200 to 300 g of wet food a day, split into several meals. Check the calories on the label and enter them in the calculator.
How do I mix wet and dry cat food?
Work out the daily calorie budget, then split it between the foods, for example 70% from wet and 30% from dry. Convert each share into grams separately, using that food's own calorie content.
How many times a day should I feed my cat?
Cats naturally eat many small meals. An adult cat does best with 3 to 4 smaller portions a day, or with food portioned into puzzle feeders, which also helps prevent weight gain.
Should a senior cat eat less?
Not necessarily. Unlike dogs, many older cats do not need less energy, and some digest protein less efficiently. It is best to set a senior cat's portion with your veterinarian, based on weight and body condition.
Sources
- 1Merck Veterinary Manual – Nutritional Requirements of Small Animalsmerckvetmanual.com
- 2Pet Nutrition Alliance – Calculating Calories Based on Pet Needs (MER/RER factors, PDF)petnutritionalliance.org
- 3dvm360 – Calculate the calories pets needdvm360.com
- 4Groves E. Nutrition requirements of senior pets. Improve Veterinary Education, 4 Feb 2019improveinternational.com
- 5Butterwick R. Calculating the energy content of pet food (Royal Canin Academy / Veterinary Focus)academy.royalcanin.com
- 6Regulation (EC) No 767/2009, Annex VII (labelling of compound feed for non-food producing animals)legislation.gov.uk
Results are estimates and do not replace advice from a veterinarian.
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