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Dog food calculator
Enter your dog’s weight and life stage to see how many calories and cups of food it needs a day.
How the calculator works
Vets start from a dog’s resting energy requirement: the calories it would burn lying still for a day. The formula is 70 × (weight in kg)0.75. Because of that 0.75 power, a 60 lb dog needs about twice the calories of a 25 lb dog, not two and a half times.
That resting number is multiplied by a factor for life stage and activity. A spayed or neutered adult needs about 1.4 to 1.6 times its resting calories, and a young puppy needs about 3 times. For weight loss, vets feed resting calories for the goal weight, not the current one.
If you enter the calories in your dog’s food, the calculator divides to give cups, cans or grams a day. Under AAFCO model rules, which most US states have adopted, dog food labels must state calories both per kg and per cup, can or piece. Look for “Calorie content” on the bag or can.
Calories a day by weight
Calories (kcal) a day from the vet formula. Real needs vary by up to about 30% either way.
| Weight | Resting | Spayed or neutered adult | Puppy, 4 months+ |
|---|---|---|---|
| 5 lb | 130 | 180–210 | 260 |
| 10 lb | 220 | 300–350 | 440 |
| 15 lb | 290 | 410–470 | 590 |
| 20 lb | 370 | 510–590 | 730 |
| 30 lb | 500 | 690–790 | 990 |
| 40 lb | 620 | 860–980 | 1230 |
| 50 lb | 730 | 1020–1160 | 1450 |
| 60 lb | 830 | 1170–1330 | 1670 |
| 70 lb | 940 | 1310–1500 | 1870 |
| 80 lb | 1030 | 1450–1660 | 2070 |
| 100 lb | 1220 | 1710–1960 | 2450 |
| 120 lb | 1400 | 1960–2240 | 2810 |
Life stage factors
Each life stage multiplies resting calories by a factor from the 2021 AAHA guidelines.
| Life stage | Times resting calories |
|---|---|
| Puppy under 4 months | 3.0 |
| Puppy 4 months to fully grown | 2.0 |
| Adult, spayed or neutered | 1.4–1.6 |
| Adult, not spayed or neutered | 1.6–1.8 |
| Adult, inactive or gains weight easily | 1.0–1.2 |
| Adult, needs to lose weight (at goal weight) | 1.0 |
| Active adult or light work | 1.6–2.0 |
| Working dog, moderate work | 2.0–5.0 |
Check the result against your dog
Any formula is a starting point. Dogs of the same weight can need noticeably more or less, and indoor or less active dogs often need less than the formula says. Weigh your dog every few weeks. If it gains or loses weight it shouldn’t, feed a little less or a little more and check again.
A dog at a healthy weight has ribs you can feel easily under a thin layer of fat and a visible waist when seen from above. Your vet can score your dog’s body condition and suggest a goal weight.
Measure the food carefully
Scooping kibble with a measuring cup is less precise than it looks. In a study by A.J. German and colleagues (Journal of Animal Physiology and Animal Nutrition, 2011), portions measured with cups ranged from 18% too little to 80% too much. A kitchen scale is more accurate: use the kcal per kg on the bag and the calculator will give grams.
Puppies
Puppies grow quickly, so their needs change from week to week. Recalculate whenever you weigh your puppy. Large and giant breed puppies should stay lean while growing and should not get extra calcium, so feed a food made for large-breed puppies and avoid supplements unless your vet recommends them.
Pregnant and nursing dogs
This calculator is not for them. A pregnant dog needs about three times her resting calories in the last three weeks, and a nursing mother can need six times or more, depending on litter size. Ask your vet how to feed her.
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Common questions
How many calories does a dog need a day?
A typical spayed or neutered 40 lb dog needs about 860 to 980 calories a day, and a 20 lb dog about 510 to 590. The table above covers other weights. Vets use these numbers as a starting point, then adjust by watching your dog’s weight and body shape.
How many cups of food should I feed my dog?
Divide your dog’s daily calories by the calories per cup printed on the bag. Foods vary a lot, so the same number of cups can mean very different amounts of food. The calculator does this for you if you enter the number from the bag.
How much should I feed a puppy?
Puppies need about three times their resting calories until 4 months old, then about twice their resting calories until they are fully grown. Because they gain weight fast, weigh your puppy every week or two and recalculate. The puppy weight calculator shows how close your puppy is to adult size.
Should I go by the feeding chart on the bag?
The chart on the bag is a reasonable starting point, but the 2021 AAHA guidelines recommend working out calories rather than relying only on the package, because feeding charts aren’t standardized. Both are estimates for an average dog. If your dog gains or loses weight it didn’t need to, change the amount a little and check again in a few weeks.
How many treats can my dog have?
Treats and extras should make up no more than 10% of daily calories, according to the 2021 AAHA nutrition guidelines. The calculator shows that amount for your dog.
Sources: Cline MG et al., “2021 AAHA Nutrition and Weight Management Guidelines for Dogs and Cats”, JAAHA 2021;57(4):153–178. Sanderson SL, “Nutritional Requirements of Small Animals”, Merck Veterinary Manual (updated September 2024). An estimate to start from, not veterinary advice. Dogs with a health condition should follow their vet’s plan.