How this calculator works
This tool uses the Resting Energy Requirement (RER) formula commonly used by veterinarians:
RER = 70 × (body weight in kg) 0.75
RER is then multiplied by a factor for life stage and activity level to estimate daily calorie needs (Maintenance Energy Requirement, or MER). A neutered adult dog at normal activity typically needs about 1.6× RER, while an active or working dog can need 2× RER or more.
How to use the result
Check your dog food's label for calories per cup or per can, then divide the daily calorie target by that number to get a rough daily feeding amount. Split it across 2 meals per day for most adult dogs. Every dog's metabolism is different — use this as a starting point and adjust based on your dog's body condition over a few weeks.
This tool is for general information only and isn't a substitute for advice from your veterinarian, especially for puppies, senior dogs, or dogs with medical conditions.
Quick reference: daily calories by weight
Resting Energy Requirement (RER) is what the body burns at rest. The columns after it apply the life-stage factors this calculator uses.
| Weight | RER | Neutered adult (1.6×) | Very active (2.0×) | Senior (1.4×) |
|---|---|---|---|---|
| 10 lbs | 218 | 348 | 435 | 305 |
| 20 lbs | 366 | 585 | 732 | 512 |
| 30 lbs | 496 | 794 | 992 | 694 |
| 40 lbs | 615 | 985 | 1,231 | 862 |
| 50 lbs | 727 | 1,164 | 1,455 | 1,018 |
| 70 lbs | 936 | 1,498 | 1,873 | 1,311 |
| 90 lbs | 1,131 | 1,809 | 2,261 | 1,583 |
| 120 lbs | 1,403 | 2,244 | 2,806 | 1,964 |
All values are kilocalories per day, rounded. They come from the same formula the calculator runs, so the table and the tool will always agree.
Frequently asked questions
How many calories does my dog need per day?
It depends on weight first and lifestyle second. A neutered 50 lb adult at normal activity needs roughly 1,164 calories a day, while the same dog working or training hard could need about 1,455. Enter the weight above for a figure specific to your dog.
Why does the formula use kilograms and an exponent?
Because energy use does not scale in a straight line with body weight. A dog twice as heavy does not burn twice the calories, so the formula raises weight in kilograms to the power of 0.75, a standard metabolic scaling used across veterinary nutrition. Pounds are converted to kilograms internally, so you can enter either.
Do puppies need more calories than adult dogs?
Considerably more, pound for pound. A puppy under four months is generally fed around three times its RER, dropping to roughly twice RER from four months until it reaches adult size. Growth is expensive, and underfeeding during it carries more risk than a little extra weight.
How do I turn a calorie target into cups of food?
Find the kilocalories per cup on your food's label, usually in the fine print near the guaranteed analysis, then divide the daily target by that number. A dog needing 1,164 calories on a food with 380 kcal per cup would get about three cups a day, typically split across two meals.
What if my dog needs to lose weight?
The weight-loss setting uses a factor below maintenance, which is a starting point rather than a plan. Safe weight loss in dogs is slow, usually one to two percent of body weight per week, and rapid restriction can cause problems. Do this with your veterinarian, who can rule out conditions such as hypothyroidism first.