Cat Calorie Calculator
Daily calories for your cat from weight and life stage, with a realistic range and the amount of food that gives you.
Enter a weight to see the daily calories.
Not veterinary advice. PuppySizer gives estimates from published sources. It cannot examine your pet. For any health concern, ask your own veterinarian. Read the full disclaimer.
The formula
Resting energy requirement: RER = 70 × (body weight in kg)0.75. Daily maintenance energy is RER times a factor from the Merck Veterinary Manual:
| Life stage | × RER |
|---|---|
| Kitten | 2.5 |
| Adult, spayed or neutered | 1.2 |
| Adult, not spayed or neutered | 1.4 |
| Adult, prone to weight gain | 1 |
Daily calories by weight
| Weight | Neutered adult | Intact adult | Prone to weight gain | Kitten |
|---|---|---|---|---|
| 2.0 kg (4.4 lb) | 141 kcal | 165 kcal | 118 kcal | 294 kcal |
| 3.0 kg (6.6 lb) | 191 kcal | 223 kcal | 160 kcal | 399 kcal |
| 4.0 kg (8.8 lb) | 238 kcal | 277 kcal | 198 kcal | 495 kcal |
| 5.0 kg (11.0 lb) | 281 kcal | 328 kcal | 234 kcal | 585 kcal |
| 6.0 kg (13.2 lb) | 322 kcal | 376 kcal | 268 kcal | 671 kcal |
| 8.0 kg (17.6 lb) | 400 kcal | 466 kcal | 333 kcal | 832 kcal |
A 2 kg adult cat is unusual, and a 2 kg kitten is a few months old: pick the row that matches the stage, not only the weight.
Frequently asked questions
How many calories does a cat need per day?
A 4 kg (about 9 lb) neutered adult cat comes out at about 238 kcal a day with the veterinary formula: resting energy of 198 kcal times 1.2. An intact adult is about 277 kcal, and a cat prone to weight gain about 198 kcal.
Why is a neutered cat's number lower?
The Merck Veterinary Manual builds age and neuter status into its formulas: 1.2 times resting energy for neutered adult cats against 1.4 for intact ones, and 1.0 for cats prone to weight gain. Pick the line that fits your cat, then adjust from what the scale says.
How much does a kitten need?
The same source gives 2.5 times resting energy for healthy kittens, and adds that kittens can also be fed free choice. Kittens grow quickly, so recalculate every couple of weeks from their current weight.
Is the figure exact?
No. Animals of the same weight can differ by up to 30 % in what they need, according to the Merck Veterinary Manual. Weigh your cat every two weeks, and adjust portions by about 10 % at a time.
How many treats can my cat have?
No more than 10 % of daily calories, with a complete and balanced food supplying at least 90 %, per the 2021 AAHA nutrition guidelines. Check the calories on the treat label.
My cat is overweight. What weight do I enter?
Enter the ideal weight your vet gives you. The AAHA guidelines base the calculation on ideal weight. A weight-loss plan should come from your vet, because cutting calories on a normal food also cuts nutrients.
Sources
- Nutritional Requirements of Small Animals. Merck Veterinary Manual. Read 2026-11-08. Used for: RER = 70 x (body weight in kg)^0.75; maintenance multipliers for dogs and cats by life stage and neuter status; up to 30 % individual variation.
- 2021 AAHA Nutrition and Weight Management Guidelines for Dogs and Cats. Journal of the American Animal Hospital Association 57(3):153-178. Read 2026-11-08. Used for: A complete and balanced diet should supply at least 90 % of calories; treats and other foods no more than 10 %.
Facts last checked against their sources on November 8, 2026. Read how the numbers are built on the sources and method page.