How Many Calories Should My Dog Eat Per Day?
Wondering how many calories your dog should eat per day? This free calculator gives you an estimate of your dog's daily calorie needs in seconds, using the same RER (resting energy requirement) and MER (maintenance energy requirement) formulas veterinarians rely on. Just enter your dog's weight and life stage, and you'll see their estimated daily calories — plus an optional cups-per-day conversion if you know your food's calorie density.
Enter your dog's details
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How to use this calculator
Enter your dog's weight in pounds or kilograms, then choose the life stage / activity option that fits best. If your dog needs to lose weight, enter the target weight your vet wants them to reach, and pick the weight-loss option — the formula works on the goal weight, not the current overweight one. If you know the kcal per cup printed on your dog food bag, enter it to also see an approximate cups-per-day figure.
Results update instantly as you change anything. Try comparing options — for example, see how much the daily number shifts between "inactive" and "active," or what a 5 lb change in weight does to the calorie target.
How it works
Veterinarians answer "how many calories should my dog eat per day?" in two steps. First they compute the resting energy requirement (RER) — the calories a body burns at rest. It scales with metabolic body weight, not straight body weight:
RER = 70 × (body weight in kg)0.75
Next they multiply the RER by a life-stage factor to get the maintenance energy requirement (MER) — the estimated daily calories:
- Weight loss: ×1.0 (of target weight)
- Inactive / obesity-prone: ×1.2–1.4 (calculator uses ×1.3)
- Adult, spayed/neutered: ×1.6
- Adult, intact: ×1.8
- Active / working dog: ×2.0–5.0 (calculator uses ×3.0)
- Puppy under 4 months: ×3.0; puppy 4 months to adult: ×2.0
These factors come from published NRC/AAHA veterinary feeding guidelines and are the industry standard for calorie planning. They are still estimates: a couch-potato senior of a breed that runs lean can differ by 20–25% from the formula either way. The optional cups-per-day figure is simply daily calories ÷ your food's kcal per cup, rounded to the nearest quarter cup.
This page answers how many calories your dog needs per day. When you want to turn that number into actual food — cups per day from your specific bag plus a feeding schedule — see our Dog Food Portion Calculator.
Frequently asked questions
What is the difference between RER and MER?
RER (resting energy requirement) is the calories a dog's body needs at rest, calculated as 70 × (body weight in kg)^0.75. MER (maintenance energy requirement) is the RER multiplied by a life-stage factor — 1.6 for a neutered adult, 1.8 for an intact adult, 1.0 for weight loss, and 2.0 to 5.0 for active or working dogs. The MER is your dog's estimated daily calorie need.
How is this different from the Dog Food Portion Calculator?
This calculator answers how many calories your dog needs per day — the energy target. The Dog Food Portion Calculator takes that idea one step further and converts the calorie target into actual cups of your specific food per day, plus a feeding schedule. Use this page to learn the calorie number; use the portion calculator to plan meals.
Should I enter my dog's current weight or target weight?
Enter the weight you want your dog to be — their ideal or target weight. If your dog is overweight and you select the weight-loss factor, use the goal weight rather than the current weight. For weight maintenance, use their current healthy weight. Puppies are still growing, so use their current weight and recheck the number monthly as they grow.
How many calories should my dog eat per day to lose weight?
For weight loss, vets typically feed the RER (multiplier ×1.0) calculated at the dog's ideal target weight — not the current overweight weight. Because calorie restriction should be gradual and supervised, check with your veterinarian before starting a weight-loss plan, and expect to adjust by 10 to 20 percent based on how your dog responds.
How accurate is this dog calorie calculator?
It is a solid estimate built on standard veterinary energy formulas, but individual dogs can vary by 20 to 25 percent in either direction. Breed, body condition, metabolism, spay/neuter status, climate, and daily routine all shift real calorie needs. Treats and table scraps should stay under 10 percent of the daily total. Confirm the number with your vet, especially for puppies, seniors, pregnant or nursing dogs, and any health condition.