Cat Food Calculator Cat Food Calculator
How much should you feed your cat? Enter their weight to find out — free 🐾
Enter your cat's weight and life stage to instantly calculate the daily calories and amount of food (in grams) they need. Based on the standard veterinary formula (RER × life-stage factor).
Result
Daily calories needed: kcal
Dry food: g/day
Wet food alone already exceeds the daily calories. Reduce the number of servings.
This result is a general estimate. Actual needs vary with your cat's metabolism and activity. Adjust by watching weight changes over time, and consult your veterinarian if you have any concerns.
How it works
This calculator uses the following formula:
- Resting Energy Requirement RER = 70 × body weight (kg)0.75
- Daily Energy Requirement DER = RER × life-stage factor
- Amount (g) = DER × 100 ÷ the food's calories per 100 g
You can enter weight in kilograms or pounds, and food energy as kcal/kg or kcal/100g — whichever your bag shows.
Frequently asked questions
How do I calculate how much to feed my cat?
Find the resting energy requirement (RER = 70 × body weight^0.75), multiply it by a life-stage factor to get the daily calories (DER), then divide by the food's calories per 100 g to get grams per day.
How is it different for kittens?
Growing kittens need roughly 1.5–2.5× the calories per body weight of an adult. Use a factor of 3.0 (up to 4 months), 2.5 (4–6 months), or 2.0 (7–12 months) depending on age.
What if I also feed wet food?
Subtract the wet food's calories from the daily requirement, then divide the remainder by the dry food's calorie density. The wet-food option does this automatically.
Is it safe to feed exactly the calculated amount?
The result is an estimate. A cat's real needs vary with metabolism and activity, so adjust by watching weight changes. For cats with health conditions, follow your veterinarian.