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Calculate your cat's daily calorie needs and portion sizes using veterinary RER/MER formulas. Supports wet, dry, and mixed food, body condition scoring, and metric/imperial units. Get portions in grams, cups, and ounces.
Daily Calorie & Portion Guide
Ribs palpable with slight fat cover; visible waist
~350 kcal/cup (dry kibble)
10% (11 kcal)
This calculator uses two veterinary formulas to determine your cat's daily calorie needs:
Step 1: Calculate RER (Resting Energy Requirement)
RER = 70 x (body weight in kg)^0.75
This is the calories your cat burns at complete rest, breathing, circulation, organ function.
Step 2: Calculate MER (Maintenance Energy Requirement)
MER = RER x Activity Factor x BCS Factor
Activity factors: Indoor 1.2, Normal 1.3, Active 1.4, Kitten 1.6, Senior 1.1, Pregnant 2.0. BCS adjusts for weight status.
Step 3: Deduct Treat Calories
Food Calories = MER - Treat Calories (10% of MER)
Treats should be no more than 10% of daily calories. Adjust the slider above.
Step 4: Convert to Portions
Portion = Food Calories / Calorie Density of Food
Dry: ~350 kcal/cup. Wet: ~25 kcal/oz. Mixed: ~300 kcal/cup. Check your food label for exact values.
Source: NRC (National Research Council) Nutrient Requirements of Cats and AAFCO (Association of American Feed Control Officials) guidelines.
General guidelines for average indoor adult cats. Use the calculator above for personalized recommendations.
| Weight | Daily Calories | Dry Food (cups) | Wet Food (5.5oz cans) |
|---|---|---|---|
| 5 lbs (2.3 kg) | 120-150 kcal | 1/3 - 1/2 cup | 1 - 1.5 cans |
| 7 lbs (3.2 kg) | 160-200 kcal | 1/2 - 3/4 cup | 1.5 - 2 cans |
| 8 lbs (3.6 kg) | 180-220 kcal | 1/2 - 3/4 cup | 1.5 - 2 cans |
| 10 lbs (4.5 kg) | 200-260 kcal | 3/4 - 1 cup | 2 - 2.5 cans |
| 12 lbs (5.4 kg) | 240-300 kcal | 3/4 - 1 cup | 2.5 - 3 cans |
| 14 lbs (6.4 kg) | 270-340 kcal | 1 - 1.25 cans | 2.5 - 3.5 cans |
| 16 lbs (7.3 kg) | 300-380 kcal | 1 - 1.25 cups | 3 - 4 cans |
Based on ~350 kcal/cup dry food and ~200 kcal per 5.5oz wet food can. Actual values vary by brand, always check the label.
Many vets recommend a combination of both. The calculator supports wet, dry, and mixed feeding. Check your specific food label for calorie counts, as brands vary significantly.
Body Condition Score (BCS) is a 1-9 scale used by veterinarians to assess weight status. It adjusts calorie recommendations in the calculator.
| BCS | Category | What You'll See/Feel | Calorie Adjustment |
|---|---|---|---|
| 1-3 | Underweight | Ribs, spine visible; no fat cover; prominent hip bones | +20% calories |
| 4-5 | Ideal | Ribs palpable with slight cover; visible waist from above; tucked belly | No adjustment |
| 6-7 | Overweight | Ribs hard to feel; no visible waist; rounded belly | -15% calories |
| 8-9 | Obese | Ribs not palpable; no waistline; hanging belly pad | -30% calories |
Source: Association for Pet Obesity Prevention (APOP) and Purina Body Condition Scoring System.
Most adult indoor cats need 200-300 calories per day, depending on weight and activity. A 10 lb (4.5 kg) indoor cat typically needs about 200-220 kcal/day. Use the calculator above for a personalized recommendation based on your cat's weight, activity level, and body condition.
Content Updated At : 30/08/2026
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