Food Portion Calculator
Built on the same Resting Energy Requirement equation veterinarians use, this tool turns your dog's weight and lifestyle into a daily calorie target — and a practical number of cups per meal.
Your dog
Check your food's label — most kibble is 350–450 kcal/cup.
Daily feeding target
Estimated daily calories
1,164 kcal per day
- Food per day2.9 cups
- Per meal (2 meals/day)1.5 cups
- Resting energy (RER)727 kcal
- Total multiplier1.6× RER
Estimates only. Individual metabolism varies by up to ±50%, and puppies, pregnant or nursing dogs, and dogs with medical conditions need veterinary guidance. Recheck body condition every two weeks and adjust portions by 10% at a time. Always consult your veterinarian before changing your dog's diet.
How the portion calculator works
The math starts with the Resting Energy Requirement (RER), the calories a dog burns at complete rest:RER = 70 × (weight in kg)^0.75. The exponent means calorie needs don't scale linearly with weight — a 20 kg dog needs far less than twice the food of a 10 kg dog. The RER is then multiplied by a life-stage factor from standard veterinary nutrition references: 3.0 for puppies under four months, 2.0 for older puppies, 1.6 for neutered adults, 1.8 for intact adults, and roughly 1.4 for typical seniors. Activity level and body condition adjust that figure up or down; for an overweight adult the total is capped at 1.0 × RER, the standard starting point for a supervised weight-loss plan.
Calories only become useful when translated into food, so the calculator divides the daily target by your food's calorie density. This matters more than most owners expect: two popular kibbles can differ by 100+ kcal per cup, which means the "same" two-cup serving can be a 25% calorie swing. Always enter the value printed on your specific bag, and re-weigh your dog monthly — a measuring cup and a bathroom scale are the two cheapest health tools in dog ownership.
Limitations
RER-based formulas are population averages. Real-world metabolism varies with genetics, ambient temperature, and health status, so treat the output as a starting point and let body condition be the referee: you should be able to feel your dog's ribs with light pressure and see a waist from above. Treats count — keep them under 10% of daily calories, and subtract them from the meal allowance. Any dog that is pregnant, nursing, under 8 weeks old, or managing a condition like diabetes or kidney disease needs a feeding plan from a veterinarian, not a calculator.
Feeding FAQ
How many calories does my dog need per day?
It depends on weight, age, activity, and reproductive status. Vets start with the Resting Energy Requirement — RER = 70 × (body weight in kg)^0.75 — then multiply by a life-stage factor. A neutered adult dog of average activity needs about 1.6 × RER, while a growing puppy can need 2–3 × RER.
How do I find my food's kcal per cup?
Every commercial dog food sold in the US must list caloric content on the label, usually as "kcal/cup" or "kcal/kg" in the guaranteed analysis panel. Most dry kibble falls between 350 and 450 kcal per cup; the calculator defaults to 400 and lets you adjust.
How many meals per day should I feed?
Adult dogs do well on two measured meals. Puppies under six months should eat three to four times daily because of their small stomachs and high energy demand. Free-feeding (leaving food out all day) is strongly associated with obesity and is not recommended.
My dog is overweight — how fast should it lose weight?
A safe target is 1–2% of body weight per week, typically achieved by feeding roughly the RER (1.0×) of the dog's ideal weight rather than its current weight. Crash dieting is dangerous, especially in small dogs — any weight-loss plan should be set with your veterinarian, and this calculator is not a substitute for that conversation.