The formula
Resting energy (RER) = 70 × body weight in kg^0.75. Multiply by a life-stage factor from the Pet Nutrition Alliance:
| Cat | Factor |
|---|---|
| Neutered or spayed adult | 1.2 × RER |
| Intact adult | 1.4 × RER |
| Inactive or gains weight easily | 1.0 × RER |
| Weight loss (with your vet) | 0.8 to 1.0 × RER |
| Growing kitten | 2 to 3 × RER |
Calories by weight (neutered adult)
| Weight | RER | Daily calories (1.2 × RER) | Treat budget (10%) |
|---|---|---|---|
| 6 lb | 148 kcal | 178 kcal | 18 kcal |
| 8 lb | 184 kcal | 221 kcal | 22 kcal |
| 10 lb | 218 kcal | 261 kcal | 26 kcal |
| 12 lb | 249 kcal | 299 kcal | 30 kcal |
| 14 lb | 280 kcal | 336 kcal | 34 kcal |
| 16 lb | 310 kcal | 371 kcal | 37 kcal |
Turning calories into food
Your cat food label lists calories as kcal per can or kcal per cup. Divide the daily calories (minus treats) by that number. The cat food calculator does it for you.
Every cat is different. Weigh yours every few weeks and adjust, and ask your vet before a weight-loss plan.
Source: Pet Nutrition Alliance, "Calculating Calories Based on Pet Needs".
