Dog Daily Calorie Calculator
Find your dog's daily calorie needs with the vet RER and MER formula. Enter weight and life stage to get resting and maintenance energy in kcal per day.
Updated 2026-06-14 · Free · No sign-up · Runs privately in your browser
Show the formula & steps
How the Dog Daily Calorie Calculator Works
This tool estimates how many calories (kcal) your dog needs each day using the same two-step method veterinarians use. Enter your dog’s weight (in kilograms or pounds) and choose a life stage or activity level, and it returns both the resting energy requirement (RER) and the daily maintenance energy requirement (MER).
The Formula
The calculation has two parts. First, find the resting energy requirement — the energy burned at rest:
RER = 70 × weight(kg)^0.75
Then multiply by a life-stage factor to get the maintenance energy requirement, the calories your dog actually needs over a normal day:
MER = RER × factor
The factor reflects activity and physiology — a couch-loving neutered adult uses about 1.6, while a hard-working sled dog can use 2.0 to 5.0.
Worked Example
For a 20 kg neutered adult dog:
- Convert weight: already 20 kg.
- RER = 70 × 20^0.75 = 70 × 9.457 = ≈ 662 kcal/day
- MER = 662 × 1.6 = ≈ 1,059 kcal/day
So this dog needs roughly 1,059 calories per day to maintain a healthy weight.
Life-Stage and Activity Factors
The factor you choose has a large effect on the result. These are the standard veterinary multipliers:
| Life stage / activity | Factor (× RER) |
|---|---|
| Weight loss | 0.8 – 1.0 |
| Inactive / obese-prone | 1.2 – 1.4 |
| Neutered adult | 1.6 |
| Intact adult | 1.8 |
| Active / working dog | 2.0 – 5.0 |
| Puppy 0–4 months | 3.0 |
| Puppy 4 months–adult | 2.0 |
Turning Calories Into Food
Daily calories tell you how much to feed once you know your food’s energy density. Check the kcal per cup (dry) or kcal per can (wet) printed on the label, then divide your dog’s daily calories by that number. For example, 1,059 kcal ÷ 340 kcal per cup ≈ 3.1 cups per day.
Important Notes
These figures are estimates for healthy adult dogs. Pregnancy, lactation, illness, recovery from surgery, and certain breeds shift requirements significantly. Always weigh your dog regularly, watch body condition, and confirm a feeding plan with your veterinarian — especially for puppies, seniors, and dogs on a weight-management program.
Frequently asked questions
How many calories does my dog need per day?+
Calculate the resting energy requirement, RER = 70 × body weight in kg raised to the power 0.75, then multiply by a life-stage factor. A 20 kg neutered adult needs about 662 × 1.6 ≈ 1,059 kcal per day.
What is the difference between RER and MER?+
RER (resting energy requirement) is the calories a dog burns at complete rest. MER (maintenance energy requirement) is the total daily calories needed for a normal lifestyle, found by multiplying RER by an activity or life-stage factor.
Why does the calculator use weight to the power 0.75?+
Energy use does not scale in a straight line with body weight; it scales with metabolic body size. Raising weight in kilograms to the power 0.75 reflects that a 40 kg dog needs less than twice the calories of a 20 kg dog.
What life-stage factor should I use for a puppy?+
Use a factor of about 3.0 for puppies up to 4 months old and about 2.0 from 4 months to adulthood, because growing puppies need far more energy per kilogram than adult dogs.
Should I reduce calories for an overweight dog?+
Yes. For weight loss, vets often feed at the RER for the dog's ideal target weight, or use a factor of around 0.8 to 1.0 of RER, and re-check weight every two to four weeks. Ask your vet for a tailored plan.