How many calories does my dog need?
Enter your dog's weight, age and activity. Instead of one blended number, this shows every published method that applies, because the sources disagree and it is more useful to see by how much.
| Method | kcal/kg0.75 | kcal/day |
|---|
A dog that will not lose weight on a controlled ration needs hypothyroidism and Cushing's disease ruled out. Neither responds to a smaller bowl.
Pet food labels carry a "Calorie Content" statement giving kilocalories per kilogram and per familiar unit, such as per cup or per can. Divide the daily figure above by the calories per cup and you have the amount to feed.
Then subtract the treats. A large dental chew can be a tenth of a small dog's daily allowance, and treats are where carefully built feeding plans quietly fall apart.
Why this shows a range and not an answer
Every method here starts from the same base. You cannot scale calories straight off bodyweight, because a big dog burns less per kilo than a small one, so the tables use metabolic bodyweight: weight in kilograms raised to the power 0.75. Resting energy requirement is then 70 × (weight in kg)0.75. For a 20 kg dog that is about 662 calories a day, which is the floor rather than the feeding amount.
After that the sources part company, and the shape of the disagreement matters more than the numbers:
- FEDIAF sorts adult dogs by activity level and by age. It publishes no neuter factor at all.
- Merck sorts adult dogs by neuter status. It publishes no activity tiers at all.
- Measured pet dogs come in below both. Pedrinelli's 165 weight-stable pets averaged 86.1, against FEDIAF's headline 110.
A calculator that asks you for activity and neuter status and then returns one number has stitched two models together and added an assumption neither body made: that the neuter effect is multiplicative and independent of activity. Nobody has tested that. So this tool reports each method separately, names who published it, and shows the span.
The headline figure is the lowest of them. That is not caution for its own sake, it is FEDIAF's own instruction: "To avoid overfeeding and the risk of obesity, it may be better to start from a lower calculated MER and add as needed to maintain optimal body weight." The same annex admits its recommendations "may overestimate energy needs by 10 to 60%", because they assume an amount of exercise many dogs never get.
The number that should worry you most
Merck notes that any given dog "may require as much as 30% more or less" than the calculated figure. The Pet Nutrition Alliance says 50%. The gap between two dogs of the same weight is wider than any adjustment these tables ask you to make. Which is why the last step matters more than the sum: weigh monthly, feel the ribs, and adjust by 10% at a time.
The full working, every source, and the parts nobody has measured are in how many calories does my dog need. For a growing puppy the calculation is different, and how much to feed a puppy covers it. The hands-on way to judge whether you got it right is in is my puppy overweight, and it works just as well on an adult.
Questions people ask
How many calories does my dog need a day?
For a moderately active adult dog, FEDIAF’s figure is 110 calories per kg of bodyweight to the power 0.75, which is about 1,040 calories for a 20 kg dog. For a dog walked less than an hour a day it is 95, or about 900 calories. Treat either as a starting point. The same guidelines warn the numbers can overestimate what a dog really needs by 10 to 60%.
Why does this calculator show a range instead of one number?
Because the published sources genuinely disagree, and they do not even disagree along the same axis. FEDIAF sorts adult dogs by activity and by age and publishes no neuter factor at all. Merck sorts by neuter status and publishes no activity tiers. A calculator that asks for both and returns a single number has quietly invented a third model that assumes the neuter effect is multiplicative and independent of activity, which nobody has tested. Showing every applicable method with its source is the honest version.
Should I use my dog’s current weight or its target weight?
Target weight, if your dog is overweight. AAHA’s 2021 guidelines say to base feeding calculations on current weight if the dog is at or below its ideal weight, and on ideal bodyweight if it is overweight or obese, so that you are feeding the lean mass the dog actually has rather than the fat it is carrying. Get this backwards and you feed an overweight dog exactly enough to stay overweight, which is a larger error than picking the wrong multiplier.
Do neutered dogs need fewer calories?
The direction is well supported; the size of the drop is not. Merck’s convention works out at about 11% less. One large review reported neutered dogs about 25% below intact dogs, but that rested on only two all-neutered treatment groups against seven all-intact, 61 of 70 groups did not record neuter status at all, and the authors noted the difference was not evident in pet or working dogs. FEDIAF publishes no neuter factor whatsoever.
Do senior dogs need fewer calories?
Usually, but the evidence is weaker than the tables suggest. FEDIAF publishes 95 for dogs over seven against 110 for dogs aged three to seven, about 14% less. Against that, a review of 713 dogs found no age effect at all, the widely quoted 20% figure traces to a paper that calls the decline an assumption, and FEDIAF’s own advisory board states there are no experimental data on the energy requirements of older dogs. Some illnesses push needs up rather than down. Feed to body condition, not to a birthday.
How many calories should a dog eat to lose weight?
Roughly 60 to 80 calories per kg of target weight to the power 0.75, depending on sex and neuter status. Those are the allocations used in a study of 926 overweight dogs: intact males 80, neutered males and intact females 70, neutered females 60. Expect about 0.9% of bodyweight a week, which is what that study actually achieved, rather than the 1–2% commonly promised. A dog that will not lose weight on a controlled ration needs hypothyroidism and Cushing’s disease ruled out.
How accurate is a dog calorie calculator?
Less precise than the decimal places imply. Merck notes any given dog may require as much as 30% more or less than the calculated figure, and the Pet Nutrition Alliance says 50%. That spread between two dogs of the same weight is wider than any adjustment these tables ask you to make for activity, age or neuter status. The sum is where you start; body condition over the following month is what actually settles it.
This is not veterinary advice. These figures are starting points drawn from published guidelines, for general information and education. They are not a feeding prescription for your individual dog, and the sources they come from say plainly that they can overestimate what a real dog needs.
Talk to your vet before starting a weight-loss plan, and before changing the diet of a dog that is unwell, pregnant, nursing or on medication. A dog that will not lose weight on a controlled ration needs hypothyroidism and Cushing's disease ruled out, and neither responds to a smaller bowl.