Pet Food Calculator
Calculate the exact daily caloric energy and gram food portion sizes for your dog or cat. Uses World Small Animal Veterinary Association (WSAVA) metabolic formulas to prevent pet obesity and maintain optimal body condition.
Current or target body weight in kilograms (1 kg = 2.205 lbs)
Species metabolic baseline
Metabolic Energy Requirement multiplier (MER factor)
Metabolizable energy printed on your pet food bag (typically 3,400–4,000 kcal/kg for dry kibble)
Total daily food quantity to measure across all meals
How to Use This Calculator
- Weigh your pet and enter their current weight in kilograms.
- Select whether your pet is a dog or cat.
- Select their reproductive status, age, and activity level.
- Enter the kcal/kg listed on the guaranteed analysis label on your pet food bag.
- Weigh the recommended daily grams on a digital kitchen scale.
Formula & Calculation Methodology
Veterinary clinical nutrition relies on Kleiber’s Law of allometric metabolic scaling. Resting Energy Requirement (RER) is calculated from body surface mass (weight^0.75) and multiplied by the physiological life stage factor.
Worked Example
10 kg neutered adult dog eating 3,600 kcal/kg kibble
4 kg indoor neutered cat eating 3,800 kcal/kg dry food
Frequently Asked Questions
Why should I weigh pet food with a scale instead of using measuring cups?↓
Veterinary studies show that volumetric measuring cups can overestimate pet kibble by 20% to 40% due to kibble shape and settling, leading to gradual unintended weight gain.
What is RER versus MER in veterinary nutrition?↓
RER (Resting Energy Requirement) is the bare baseline energy needed to sustain life at rest. MER (Maintenance Energy Requirement) scales RER to account for movement, thermal regulation, digestion, and life stage.
How do treats fit into daily calories?↓
Veterinary nutritionists recommend that treats, biscuits, and table scraps never exceed 10% of your pet’s total daily caloric allowance, with the remaining 90% coming from complete and balanced food.
What is a limitation of standard metabolic equations?↓
Metabolic rates vary by breed genetics, neutering age, ambient climate, and muscle-to-fat body composition; monitor your pet’s body condition score (BCS) and adjust portions accordingly.
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Source Citation & Disclaimer
Informational tool only; not licensed tax, legal, or financial advice.