A 30 kg (66 lb) neutered adult has an RER of about 897 kcal and needs about 1,436 kcal a day.
How the dog food calculator works
DogFoodCalc first converts the weight to kilograms (1 kg = 2.205 lb) and works out the resting energy requirement: 70 × kg0.75. It multiplies that by the factor for the life stage you pick to get the daily energy requirement. For weight loss it uses the target weight with a factor of 1.0. The treat percentage is taken off, and the remaining calories are divided by the kcal per cup and the kcal per kg on your food to give cups and grams, then split across meals.
Life-stage factors
| Dog | × RER |
|---|---|
| Puppy under 4 months | 3 |
| Puppy 4–12 months | 2 |
| Adult, spayed/neutered | 1.6 |
| Adult, intact | 1.8 |
| Inactive or overweight-prone | 1.2 |
| Senior | 1.4 |
| Weight loss (at target weight) | 1 |
| Light work | 2 |
| Moderate work | 3 |
| Heavy work | 5 |
Daily calories by weight
| Weight | RER | Neutered adult | Cups (380 kcal) | Puppy 4–12 mo |
|---|---|---|---|---|
| 5 lb (2.3 kg) | 129 kcal | 207 kcal | 0.5 | 259 kcal |
| 10 lb (4.5 kg) | 218 kcal | 348 kcal | 0.9 | 435 kcal |
| 20 lb (9.1 kg) | 366 kcal | 585 kcal | 1.5 | 732 kcal |
| 30 lb (13.6 kg) | 496 kcal | 794 kcal | 2.1 | 992 kcal |
| 40 lb (18.1 kg) | 615 kcal | 985 kcal | 2.6 | 1,231 kcal |
| 50 lb (22.7 kg) | 727 kcal | 1,164 kcal | 3.1 | 1,455 kcal |
| 60 lb (27.2 kg) | 834 kcal | 1,335 kcal | 3.5 | 1,668 kcal |
| 80 lb (36.3 kg) | 1,035 kcal | 1,656 kcal | 4.4 | 2,070 kcal |
| 100 lb (45.4 kg) | 1,223 kcal | 1,958 kcal | 5.2 | 2,447 kcal |
| 120 lb (54.4 kg) | 1,403 kcal | 2,244 kcal | 5.9 | 2,806 kcal |
Factors are the commonly used veterinary starting points; individual dogs vary by 20–30% or more with breed, coat, climate and activity. Check body condition every few weeks and ask your vet about puppies, pregnant or nursing dogs, and dogs with medical conditions.
Frequently asked questions
How many calories does a dog need per day?
Roughly 400–600 kcal for a 20 lb neutered adult, 1,000–1,300 for a 50 lb dog and 1,500–1,800 for an 80 lb dog, depending on activity.
What is the RER formula for dogs?
RER = 70 × (body weight in kg)^0.75. For a 10 kg dog that is about 394 kcal.
Why do neutered dogs need fewer calories?
Neutering lowers energy needs, so the factor drops from about 1.8 to 1.6 × RER.
Is DogFoodCalc free?
Yes, with no sign-up or ads.
Is this veterinary advice?
No. It uses standard formulas for an estimate; your vet can tailor it to your dog.