Pet Care Calculators
Cat Food Portion Calculator
Use this cat food portion calculator to estimate how much to feed your cat each day. It calculates daily calories from your cat's weight and life stage, then shows roughly how much dry food (in cups) or wet food (in cans) that equals.
Last reviewed: June 2026
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Your result will appear here after you press Calculate.
Estimate only. A typical 3 oz can of wet food is about 90 kcal; check your brand. Treats should stay under 10% of daily calories.
Formula used
The calculator uses the standard veterinary energy formula for cats:
- Resting Energy Requirement (RER) = 70 × (body weight in kg)^0.75
- Daily calories (MER) = RER × life-stage factor
- Factors: neutered adult 1.2, intact 1.4, inactive 1.0, kitten 2.5, weight loss 0.8, pregnant/nursing 2.0
- Dry food per day = daily calories ÷ calories per cup
Worked examples
10 lb neutered indoor cat
A 10 lb (4.5 kg) cat has an RER of about 217 kcal. As a neutered adult (×1.2) that's roughly 260 kcal/day — about 0.87 cups of a 300 kcal/cup dry food, or just under three 90-kcal cans of wet food.
8 lb inactive cat for weight management
An 8 lb (3.6 kg) inactive cat needs about 185 kcal/day (×1.0). For supervised weight loss your vet may target a lower amount based on ideal body weight.
How to use this calculator
- Enter your cat's current weight in pounds or kilograms.
- Choose the life stage that fits your cat.
- Enter your dry food's calories per cup (from the bag).
- Press Calculate to see daily calories and how much dry or wet food that equals.
Reference chart
| Weight | RER (kcal) | Daily calories |
|---|---|---|
| 6 lb (2.7 kg) | 147 | ≈ 175 |
| 8 lb (3.6 kg) | 180 | ≈ 215 |
| 10 lb (4.5 kg) | 217 | ≈ 260 |
| 12 lb (5.4 kg) | 248 | ≈ 300 |
| 15 lb (6.8 kg) | 294 | ≈ 350 |
Frequently asked questions
How much should I feed my cat per day?
Most adult indoor cats need roughly 180–280 calories per day, depending on weight and activity. This calculator estimates daily calories from your cat's weight and life stage, then converts to cups of dry food or cans of wet food using the calories in your specific product.
Is wet or dry food better for portion control?
Both can work. Wet food is lower in calories per gram and adds moisture, which many cats benefit from. Dry food is calorie-dense and easy to over-pour. Measure either one against a calorie target rather than free-feeding, and split into 2–3 meals.
How many cans of wet food should I feed my cat?
Divide your cat's daily calorie target by the calories per can. A typical 3 oz can is about 90 kcal, so a cat needing 260 kcal would eat roughly three cans a day. Always check your brand's label, as calories per can vary widely.
How do I feed a kitten?
Kittens need far more energy than adults — the calculator uses a factor of 2.5 for growth. Feed a food labeled for kittens or all life stages, offer several small meals a day, and follow your veterinarian's guidance as your kitten grows.
My cat needs to lose weight — what should I do?
Select the “Weight loss” option, which uses a lower factor based on ideal body weight. Feline weight loss must be slow and supervised, because rapid calorie restriction can cause a serious liver condition. Work with your veterinarian on a safe plan.
Does this replace my veterinarian's advice?
No. It's an informational estimate to help you portion food. Your veterinarian can assess body condition, rule out medical causes of weight change, and tailor feeding to your individual cat.