How many calories does your dog need each day? Use this free calculator to get a science-based estimate for your dog’s weight, age and activity level, and to see how many cups of food that means. It uses the same basic formula veterinarians use as a starting point.
How the calculator works
The calculation has two steps. First, it estimates your dog’s resting energy requirement (RER), the energy needed for basic body functions at rest, using the widely used formula RER = 70 × (body weight in kg)0.75.
Then it multiplies the RER by a factor that reflects life stage and activity to estimate the daily energy requirement. These factors are commonly used general guidelines:
| Life stage or activity | Factor × RER |
|---|---|
| Puppy under 4 months | 3.0 |
| Puppy 4 to 12 months | 2.0 |
| Adult, spayed or neutered | 1.6 |
| Adult, intact | 1.8 |
| Less active adult or senior | 1.4 |
| Very active adult | 2.0 or more |
| Weight loss (based on target weight) | 1.0 |
Why the result is only a starting point
Two dogs of the same weight can need quite different amounts of food. Metabolism, coat, climate, health conditions and even temperament all play a role. Formulas can be off by 20% or more for an individual dog. The best guide is your dog’s body over time: if your dog is gaining weight, feed a little less; if they are losing weight or seem hungry and thin, feed a little more. Our guide on how to check your dog’s body condition explains what to look for.
Tips for accurate feeding
- Find the calories per cup (kcal/cup) on your dog food bag or can. It varies a lot between brands.
- Use a real measuring cup or, even better, a kitchen scale.
- Count treats, chews and table scraps; they add up fast.
- For weight loss, enter your dog’s target weight, not their current weight, and ask your vet to set a safe pace.
- Puppies grow quickly, so recalculate every few weeks.
Related guides
- Is My Dog Overweight? How to Check Body Condition at Home
- How to Read a Dog Food Label
- How to Switch Your Dog’s Food Without an Upset Stomach
This calculator provides general estimates for healthy dogs and is not veterinary advice. Your veterinarian can recommend the right amount to feed your individual dog.