How much should I feed my cat?

Most adult indoor cats need less food than the bag suggests — often noticeably less. The honest answer is that you work out a daily calorie number, then convert it into cups or cans using the calorie content printed on your own food, because that number varies enormously between products.

Start with calories, not cups

A "cup" is not a unit of nutrition. Dry cat foods commonly run anywhere from about 350 to 500 calories per cup, so the same measuring scoop can deliver a 40% difference in energy depending on which bag you bought. Wet food is worse: two cans of identical size can be far apart, because pâtés are denser than chunks-in-gravy.

Every complete cat food sold in the US carries a calorie statement — usually written as kcal/kg and kcal/cup or kcal/can. It is often in small print on the back near the guaranteed analysis. Find it before you do anything else.

A rough daily starting point

Vets commonly start from a figure of roughly 20 calories per pound of ideal body weight per day for a neutered adult cat at a maintenance weight, then adjust based on what the cat's body actually does over the next month. It is a starting estimate, not a prescription — real requirements swing widely with age, activity, muscle mass and whether the cat is neutered.

Those cup figures shift the moment your bag's calorie density differs from 400 kcal/cup, which is why the number on your bag beats any chart. Our food portion calculator does the same arithmetic if you would rather not do it by hand.

Feed to ideal weight, not current weight

If your cat is carrying extra weight, feeding to what they weigh now simply holds them there. The target should be their ideal weight — and that is a number your vet should set, along with the rate of loss.

This matters more in cats than in dogs. Cats cannot safely be crash-dieted. Cutting a cat's intake sharply can trigger hepatic lipidosis, a serious liver condition that develops when a cat's body mobilises fat faster than the liver can process it. Weight loss in cats is a slow, supervised project — see helping an overweight cat lose weight before you change anything.

Count the treats

Treats, dental chews, the lick of yogurt, the dropped bits of chicken — all of it counts. A common working rule is that treats stay under 10% of daily calories, with the other 90% coming from a complete and balanced food. On a 200-calorie cat, 10% is 20 calories, which is a startlingly small pile of treats. If you are feeding a lot of extras, take them out of the meal portion rather than adding them on top.

Measure, don't eyeball

Use an actual measuring cup or, better, a kitchen scale. Eyeballing a scoop is the single most common reason an indoor cat gains weight quietly over two years. A gram scale removes the drift entirely and costs very little.

Split the daily amount into meals rather than dumping it in one go — see how often to feed a cat for how to divide it, and free-feeding vs measured meals for why leaving the bowl full undermines all of this.

Then adjust based on the cat

The number you calculate is a hypothesis. Test it for four to six weeks: weigh the cat, or at least run your hands over the ribs. You should be able to feel ribs under a thin layer of covering without pressing hard, and see a waist when looking down from above.

That last row matters. A cat losing weight while eating normally is a medical question, not a feeding-maths question, and it needs a vet appointment rather than a bigger bowl.

What to do next

Find the kcal figure on your bag or can tonight, work out the daily number from your cat's ideal weight, measure it with a scale, and split it across meals. Then check the cat — not the chart — in a month and adjust by small steps. If anything about appetite or weight changes suddenly, that is a vet conversation, not a portion tweak.