Cat Food Calculator
How much to feed your cat daily, by weight and life stage.
A free cat food calculator that works out a daily feeding portion using the veterinary resting-energy-requirement (RER) method, scaled by your cat's life stage and activity level (kitten, adult, weight-loss, weight-gain or senior). Enter your food's calorie density (kcal per 100 g) to get grams and cups per day, split across your chosen number of meals. Runs fully in your browser — nothing is uploaded.
About Cat Food Calculator
- Uses your own food's calorie density, so the grams/cups actually match the bag or pouch in front of you.
- Shows daily total, per-meal amount and the underlying calorie target.
- 100% free and private — nothing you enter is stored or uploaded.
How to use Cat Food Calculator
Enter your cat's weight
Type their current weight in kilograms or pounds — toggle the unit next to the field.
Pick their life stage
Choose kitten, adult (neutered/intact), weight-loss, weight-gain or senior — this sets the calorie factor.
Check the food's energy
Enter the kcal per 100 g from your food's packaging, or leave the typical default if you're not sure yet.
Read the daily portion
See grams and cups per day, split evenly across your chosen number of meals.
Popular use cases
New Kitten Owners
Get a sensible starting portion.
Weight Management
Dial food in for loss or gain goals.
Indoor Cats
Match food to a lower-activity lifestyle.
Switching Foods
Recalculate for a new food's calorie density.
Vet Visit Prep
Bring a concrete number to discuss.
Multi-Cat Households
Get a fair portion per cat.
Frequently asked questions
How much should I feed my cat per day?
Enter your cat's weight and life stage/activity level, plus your food's calorie density from the packaging. This calculator works out their resting energy requirement (RER), scales it by a life-stage factor to get a daily calorie target, then converts that into grams and cups of your specific food.
How is the daily calorie target calculated?
It uses the standard veterinary formula RER = 70 × (weight in kg)^0.75 for resting energy requirement, then multiplies by a factor for your cat's life stage and activity (for example, roughly 1.2 for a neutered adult, up to 3.0 for a young kitten, or as low as 1.0 for a weight-loss goal).
Why do I need to enter my food's kcal per 100g?
Different cat foods — especially dry versus wet — pack very different amounts of energy into the same weight. Using your actual food's calorie density (usually printed on the packaging) instead of a generic assumption makes the gram amount accurate for what you're really feeding.
Does this work for wet food, not just dry kibble?
Yes — the gram and calorie figures work for any food once you enter its correct kcal per 100 g. The "cups" figure specifically assumes dry kibble density, so for wet food rely on the grams (or the calorie target, matched against the can/pouch label) instead.
Should I feed the full amount in one meal?
Most vets recommend splitting the daily total across 2 or more meals rather than one large feeding. Set "Meals per day" to see the amount per feeding.
Is this cat food calculator free?
Yes — completely free, with no sign-up, no app to install and no data uploaded. Everything runs instantly in your browser.
Related tools — Pet calculators
- Dog Age Calculator — Your dog's age in human years — by size, not the old ×7 myth.
- Cat Age Calculator — Your cat's age in human years — the real feline formula.
- Rabbit Age Calculator — Your rabbit's age in human years — rabbits mature much faster than you'd think.
- Bird / Parrot Age Calculator — Your bird's age on a human-equivalent scale, by species.
- Dog Food Calculator — How much to feed your dog daily, by weight and life stage.
- Lifetime Pet Cost Calculator — What a pet really costs over its whole life — not just the adoption fee.