How many calories does a cat need per day?

Start from Resting Energy Requirement: RER = 70 × (weight in kg)^0.75, then multiply by a feline life-stage factor — about 1.2 for a neutered adult, 1.4 intact, 1.0 for cats prone to weight gain, 0.8 of ideal weight for weight loss, and 2.0–2.5 for kittens. A typical 4 kg neutered indoor cat needs roughly 240 kcal per day.

Why does my cat need fewer calories than the food bag suggests?

Feeding guides are averages and often generous, while most pet cats are neutered and indoors — the lowest-need group. Calculating from your cat's own weight and life stage is usually closer, and body condition over a few weeks is the final judge.

How many calories for a cat to lose weight?

A common veterinary starting point is about 0.8 × RER calculated at the cat's ideal weight, aiming for slow loss of roughly 0.5–1% of body weight per week. Weight loss in cats must be gradual — crash dieting risks a serious liver condition — so plan it with your vet.

Cat Calorie Calculator — How Many Calories Does My Cat Need Per Day?

How this calculator works

Feline nutrition uses the same starting point as canine: the Resting Energy Requirement,

RER = 70 × (body weight in kg)^0.75

multiplied by a life-stage factor. Cats' factors run lower than dogs' — a neutered indoor cat simply doesn't burn much:

Life stage	Factor × RER
Kitten, under 4 months	2.5
Kitten, 4–12 months	2.0
Neutered adult	1.2
Intact adult	1.4
Prone to weight gain	1.0
Weight loss (ideal weight)	0.8

For a typical 4 kg neutered cat that lands around 240 kcal a day — roughly one 85 g wet pouch plus 40 g of dry food, or about 65 g of dry alone. If that sounds less than your cat would vote for: correct. Indoor neutered cats are the lowest-energy group there is, and it's why so many drift upward on the scale.

Treats count inside the total. A sensible ceiling is 10% of daily calories — for a 240 kcal cat that's just ~25 kcal, which a handful of commercial treats can blow past quickly.

Once you have the kcal target, the cat food portion calculator converts it into grams, pouches and monthly cost for your specific food.

Weight loss in cats needs a vet. Cats that lose weight too fast — or stop eating — can develop hepatic lipidosis, a dangerous liver condition. If your cat needs to slim down, do it gradually (0.5–1% of body weight per week) with your vet's guidance. And this tool, as always, gives starting estimates, not medical advice.

Frequently asked questions

How many calories does a 4 kg indoor cat need?

Around 240 kcal per day for a typical neutered adult (RER ≈ 198 × 1.2). Cats prone to gaining may need closer to 200 kcal, intact cats around 275.

Why is my cat gaining weight on the bag's recommended amount?

Bag guides are generous averages, and neutered indoor cats need less than average. Recalculate from your cat's weight and life stage, weigh portions with a scale, count treats — then adjust in small steps based on body condition.

How much should my cat eat to lose weight?

A common starting point is 0.8 × RER at ideal weight, targeting slow loss of 0.5–1% of body weight per week. Because rapid loss is dangerous for cats, build the plan with your vet and recheck weight every couple of weeks.

Cat calorie calculator

How this calculator works

Frequently asked questions