Daily calories
— kcal/day
How this is calculated
Resting energy requirement: RER = 70 × (body weight in kg)0.75
Maintenance energy requirement: MER = feline life-stage factor × RER
How much should I feed my cat?
A cat is not a small dog, and feeding one to a dog calculation is the most common feeding error there is. Feline energy factors are lower at every comparable life stage. This calculator uses the feline table, and shows you the whole sum.
The difference is not cosmetic. A neutered adult dog uses a factor of 1.4–1.6;
a neutered adult cat uses 1.2–1.4. Feeding a cat to the dog figure supplies roughly
a third more food than it needs, every day. Cats are prone to obesity and it is
genuinely hard to reverse, so the error compounds quietly for years.
How much to feed
—
Important for this stage
Why the dog table does not work for cats
The resting energy requirement uses the identical equation for both species — the Pet Nutrition Alliance says so outright. That is the part people remember, and why calorie calculators get reused across species without a second thought. The life-stage factors are where the two diverge, and they diverge in a direction that matters:
| Life stage | Cat | Dog |
|---|---|---|
| Neutered adult | 1.2–1.4 | 1.4–1.6 |
| Intact adult | 1.4–1.6 | 1.6–1.8 |
| Inactive / overweight-prone | 1.0 | 1.0–1.2 |
| Weight loss | 0.8 | 1.0 |
| Growth | 2.5 | 2.0–3.0 |
For a 10 lb neutered cat: 260 kcal/day on the feline table, 348 on the canine one. A third more food, daily, to an animal whose weight gain is slow, easy to miss under a coat, and hard to reverse.
Weight loss carries a specific risk
Cats that stop eating, or lose weight too quickly, are at risk of hepatic lipidosis (fatty liver), which can be fatal. Feline weight-loss factors are deliberately conservative for this reason. Do not start a calorie-restricted diet for a cat without veterinary supervision, and contact a vet urgently if a cat stops eating for more than a day.
Judge by body condition, not the scale
Both sources say to adjust intake by monitoring body condition rather than trusting the formula. A scale does not tell you whether the cat is carrying too much fat; your hands do.
- Underweight — Ribs, spine and hip bones are visibly obvious and easy to feel with no fat cover.
- Ideal — Ribs are easy to feel under a thin fat layer, with a visible waist behind the ribs when viewed from above.
- Overweight — Ribs are hard to feel under a fat layer, the waist is absent, and the abdomen sags.
We do not turn this into a score: it means running your hands along the ribs and spine, which a form cannot do.
Frequently asked questions
How many calories does my cat need per day?
RER = 70 × (body weight in kg)^0.75, multiplied by a feline life-stage factor: 1.2 neutered adult, 1.4 intact adult, 1.0 indoor or overweight-prone, 0.8 for a supervised weight-loss plan, 2–3 for a kitten. A typical 10 lb neutered cat lands near 260 kcal/day.
Can I use a dog calorie calculator for my cat?
No. The RER equation is shared, but a neutered adult dog uses 1.4–1.6 and a neutered adult cat uses 1.2–1.4. Feeding to the dog figure supplies roughly a third more food than the cat needs, every day.
Why is the weight-loss factor so low, and is it safe?
Cats that stop eating or lose weight too quickly risk hepatic lipidosis, a fatty liver disease that can be fatal. The 0.8 factor is deliberately conservative, which is why feline weight loss should be veterinary-led. A cat that stops eating for more than a day needs a vet urgently.
Is this veterinary advice?
No. It is an educational calculator on published formulas, and the Pet Nutrition Alliance notes that individual animals can vary by up to 50% from the predicted value. Adjust using body condition, not the number alone.
Sources
- American Animal Hospital Association. Energy Requirement Calculations — 2021 AAHA Nutrition and Weight Management Guidelines for Dogs and Cats. aaha.org
- Pet Nutrition Alliance. Calculating Calories Based on Pet Needs. petnutritionalliance.org
How these sources were chosen, and what this site does not do: about & methodology.
Educational use only. Not a veterinary service, and it cannot account for your cat’s health history. Discuss feeding and weight changes with a veterinarian.