Cat Food Calculator
Calculate how much food to feed your cat daily based on weight, age, and activity level.
Get recommendations in cups, grams, and cans.
Cat food portions are calculated using veterinary formulas based on your cat’s weight, life stage, and activity level. This calculator determines daily calorie needs and converts them into cups of dry food or cans of wet food.
Step 1 — Resting Energy Requirement (RER):
RER = 70 × (body weight in kg)^0.75
This represents the calories needed just to maintain basic body functions at rest.
Step 2 — Daily Energy Requirement (DER):
DER = RER × Life Stage Factor
| Life Stage | Factor |
|---|---|
| Kitten (under 1 year) | 2.5 |
| Adult (neutered) | 1.2 |
| Adult (intact) | 1.4 |
| Active indoor cat | 1.4 |
| Overweight/weight loss | 0.9 |
| Senior (11+) | 1.1 |
What each variable means:
- Body Weight: your cat’s current weight in pounds or kilograms. The calculator converts to kg internally since the formula uses metric units.
- Life Stage: determines the activity multiplier. Kittens need the most energy per pound because they are growing rapidly. Senior and overweight cats need fewer calories.
- Food Type: dry food, wet food, or a mix of both. Each has different calorie density.
Typical calorie content of cat food:
- Dry food: ~350–400 kcal per cup (~120 grams)
- Wet food (5.5 oz / 156g can): ~150–200 kcal per can
Practical example: A 10 lb (4.5 kg) neutered adult cat. RER = 70 × 4.5^0.75 = 70 × 3.34 = 234 kcal. DER = 234 × 1.2 = 281 kcal/day. In dry food: 281 / 375 = about 0.75 cups per day. In wet food: 281 / 175 = about 1.6 cans per day.
Tips: Always split the daily amount into 2–3 meals rather than leaving food out all day (free-feeding often leads to overeating). These calorie values are averages — check your specific food’s label for its exact kcal per cup or can. If your cat is gaining or losing weight unexpectedly, consult your veterinarian to adjust portions. Fresh water should always be available, especially for cats on dry food diets.