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Cat Food Calculator

Find how much to feed your cat — daily calories (MER), cups of dry food per day, and resting energy, based on weight and life stage.

Your cat

A healthy adult cat is often 8–12 lb. Use your vet's target weight if your cat is over- or underweight.

lb
kcal/cup

Find the kcal per cup on your dry food bag — it ranges widely (about 300–500 kcal per cup).

Key takeaways

  • Feed to daily calories (MER), not a fixed cup amount.
  • RER = 70 × kg0.75; multiply by an activity factor for MER.
  • A 10 lb indoor cat ≈ 200–220 kcal/day, roughly 0.7 cup of 300-kcal dry food.
  • Kittens and pregnant cats need far more — confirm portions with your vet.

How much to feed your cat

Cat portions should be driven by calories, not the volume on the scoop. Vets estimate needs in two steps: first the resting energy requirement (RER) — the calories a cat burns at rest — then the maintenance energy requirement (MER), which scales RER up or down by life stage and activity. Once you know the daily calorie target, divide by your food's kcal per cup to get the amount to feed.

kg = weight(lb) ÷ 2.2046 RER (kcal) = 70 × kg^0.75 MER (kcal/day) = RER × activity factor Cups/day = MER ÷ kcal per cup

Cup amounts vary a lot because dry foods differ in calorie density — always read the kcal-per-cup figure on your bag rather than copying a friend's portion.

Worked example: a 10 lb indoor cat

kg = 10 ÷ 2.2046 ≈ 4.54. RER = 70 × 4.540.75218 kcal. With an indoor/neutered factor of 1.0, MER ≈ 218 kcal/day. On a 300-kcal-per-cup dry food that's about 218 ÷ 300 ≈ 0.7 cup per day, ideally split across two meals.

Activity factors for cats

Life stage / activityFactor (× RER)Notes
Weight loss0.8Below maintenance to shed weight safely
Indoor / neutered1.0Typical maintenance for most house cats
Active1.4Intact, outdoor, or very playful cats
Pregnant2.0Rising through gestation; feed kitten food
Kitten2.5Fast growth; several small meals a day

What to do with the number

Treat the daily calories as a starting point, weigh your cat's food, and adjust over a few weeks to hold a healthy body condition. For dogs, use the dog food calculator, and to check your cat's life stage see the cat age calculator.

Frequently asked questions

How much should I feed my cat?

Feed to calories (MER), not a fixed scoop. A 10 lb indoor cat needs ≈ 200–220 kcal/day, roughly 0.5–0.75 cup of dry food depending on its calorie density.

How do wet and dry food amounts compare?

Match calories, not volume. A 3 oz wet can is ≈ 70–100 kcal; dry food is ≈ 250–500 kcal per cup. If feeding both, split the daily target between them.

How many calories does a cat need per day?

Most indoor, neutered adults need ≈ 200–250 kcal/day — from RER (70 × kg^0.75) times an activity factor near 1.0.

Should I feed a kitten more than an adult?

Yes — kittens need ≈ 2–2.5× their RER for growth, so they can need more than a heavier adult. Feed a complete kitten formula in small meals.

How much should I feed an indoor cat?

Use a maintenance factor near 1.0 — about 200 kcal/day for a 10 lb cat. If it's gaining weight, move toward 0.8 and feed measured meals.

Is free-feeding or scheduled meals better?

Measured, scheduled meals control calories and reveal appetite changes. Free-feeding dry food often causes overeating and weight gain.

Resting and maintenance energy formulas follow established vet nutrition standards — see WSAVA / AAFCO guidance, reflecting NRC energy equations for cats. Reviewed by a veterinarian.

Last reviewed June 2026

Note: this is a friendly estimate, not a feeding prescription. Individual cats vary with metabolism, body condition, and health — confirm portions with your veterinarian, especially for kittens, pregnant cats, or cats with medical conditions.