Cat daily calorie needs

How it works

As with dogs, you compute the resting metabolism (RER = 70 × weight^0.75) and multiply it by a factor tied to age, neutering and activity.

Note

Most adult cats weigh between 3 and 5 kg. It's an estimate: for diets and overweight always ask your vet.

A cat isn't a small dog

It's an obligate carnivore: unlike the dog, which over time adapted to eating anything, a cat needs nutrients that exist only in meat — taurine is the best known, and a lack of it leads to heart and eyesight problems. Hence a practical consequence worth more than any calculation: vegetarian diets for cats aren't a debatable ethical choice, they're a health problem, and dog food isn't an acceptable stopgap even for a few days.

The numbers, and neutering

You start from resting metabolism and multiply by a factor. The biggest jump is neutering, which lowers the requirement by about 20-30% and in cats is particularly visible: after the operation, with the same bowl as before, the cat puts on weight within months. It's the number one cause of overweight in house cats, and it's all there, in one coefficient.

A healthy adult cat of 4 kilos generally sits at about 200 calories a day, which is less than nearly everyone expects: three quarters of a large tin, or fifty grams or so of kibble. A growing kitten wants two or three times that.

Cats eat little and often

In the wild a cat takes ten or twelve small meals a day, and that's why the simplest way to manage weight is to split the ration rather than leaving the bowl permanently full. Food-dispensing toys work even better: they stretch out mealtime, they give some activity to an animal that doesn't get much indoors, and they cut down the eating-out-of-boredom that is half the problem.

On weight loss there's a rule that with cats can't be ignored: it has to be slow. An overweight cat that abruptly stops eating, or whose ration is cut too far, risks a serious liver disease (hepatic lipidosis) that develops within days. Any diet should be set up with the vet.

Nearby tools

To turn calories into grams there is Daily kibble amount, and for dogs Dog calorie needs. For water, which with cats is a chapter of its own, Water for dogs and cats, and for dangerous foods Foods dangerous for pets.