Cat Food Portions Calculator

Estimate daily calories (RER/DER) and convert them into wet + dry food portions using your food’s calorie density.

Calories → portions Mobile-first Adjust by goal

Quick answer

What you’ll get

Daily calorie target (RER + activity/goal factor)
Portions for dry food (cups/grams) and wet food (cans/grams)
Option to split calories between wet and dry

This is a starting estimate. Your cat’s real needs can vary — adjust based on body condition and weight trend.

Current estimate

Daily calories

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Meals/day

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Per meal

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Inputs

Cat weight

Use current weight, or ideal weight if your vet recommends.

Life stage

This affects the calorie factor.

Goal & activity

Feeding goal

Activity level

Calorie target method

Use simpler “calories per lb” mode

Default uses RER/DER. Simple mode uses a practical kcal/lb estimate.

Food calories

Enter calories for your food to convert calories into portions. You can use one food or split between wet and dry.

Split between dry & wet (optional)

Split calories between dry and wet

Dry calories (%)

Wet calories (%)

Tip: If you only feed one type, turn this off.

Dry food

Calories per cup (kcal/cup) Grams per cup (g/cup)

If unknown, 100–120 g/cup is common.

Wet food

Calories per can (kcal/can) Can size (oz)

Used for “grams per day” approximation.

Portion tips (quick)

Weigh your cat weekly. Adjust if weight is drifting up or down.
Measure dry food by weight (grams) when possible for accuracy.
Treats count — keep treats to a small part of daily calories.

How this calculator works (formulas)

1) RER (resting energy requirement)

RER = 70 × (BodyWeightKg^0.75)

2) DER (daily energy requirement)

DER = RER × Factor

Factor depends on life stage, goal (maintain/loss/gain), and activity.

3) Portions

Dry cups/day = DryCalories ÷ (kcal per cup)

Wet cans/day = WetCalories ÷ (kcal per can)

FAQ

How many calories does a cat need per day?

It depends on weight, age, activity, and body condition. This calculator estimates daily calories using RER and a practical factor. Track your cat’s weight and adjust as needed.

Is measuring by cups accurate?

Cups can be inconsistent depending on kibble shape and scoop size. Weighing food in grams is usually more accurate.

Can I use this for weight loss?

Yes — choose “Weight loss” and monitor progress. Safe weight loss is usually gradual. If your cat has medical conditions, consult a veterinarian for a tailored plan.