How much should I feed my dog?
Vets work out a dog's food in two steps. First they find the resting energy requirement (RER): the calories a dog burns lying still. Then they multiply it by a factor for life stage and activity to get the daily calories, called the maintenance energy requirement (MER). Finally, divide by the calories in your food.
Daily calories = RER × life stage factor
Cups per day = daily calories ÷ kcal per cup
Life stage factors
| Dog | Factor × RER |
|---|---|
| Puppy under 4 months | 3.0 |
| Puppy 4 months to adult size | 2.0 |
| Adult, spayed or neutered | 1.6 |
| Adult, intact | 1.8 |
| Senior or less active | 1.4 |
| Inactive or gains weight easily | 1.2 |
| Weight loss | 1.0 × RER at the target weight |
| Active or working dog | 2.0 to 5.0 |
Worked example
A 50 lb (22.7 kg) neutered adult dog: RER = 70 × 22.7^0.75 = about 727 kcal. Daily calories = 727 × 1.6 = 1,164 kcal. Keeping 10% for treats leaves 1,047 kcal of food. With kibble at 380 kcal per cup, that is about 2.75 cups a day, or a little under 1.4 cups per meal.
Daily calories by weight (neutered adult)
| Weight | RER | Daily calories (× 1.6) |
|---|---|---|
| 10 lb | 218 kcal | 348 kcal |
| 20 lb | 366 kcal | 585 kcal |
| 30 lb | 496 kcal | 794 kcal |
| 50 lb | 727 kcal | 1,164 kcal |
| 70 lb | 936 kcal | 1,498 kcal |
| 90 lb | 1,131 kcal | 1,809 kcal |
Tips
- Measure with a scale. A "cup" scooped by eye can be 20% off. A kitchen scale and the kcal per kg on the bag are more accurate.
- Count the treats. Keep treats and chews under 10% of daily calories.
- Watch the body, not just the bag. You should feel the ribs easily under a thin layer of fat and see a waist from above.
- Change food slowly. Mix the new food in over 7 to 10 days.
Feeding a growing puppy? Check its expected adult size with the puppy weight calculator. For cats, use the cat food calculator.
Sources: RER and life stage factors as used in WSAVA and Pet Nutrition Alliance feeding guidance and veterinary nutrition textbooks. Individual needs vary by up to 30%.
Frequently asked questions
How many cups of food should my dog eat a day?
Work out daily calories (70 × weight in kg to the power 0.75, times the life stage factor) and divide by the kcal per cup on your bag. A 50 lb neutered adult needs about 1,160 kcal, roughly 3 cups of a 380 kcal per cup kibble, or 2.75 cups if 10% comes from treats.
How many calories does a dog need per day?
About 350 kcal for a 10 lb neutered adult, 800 kcal for 30 lb, 1,160 kcal for 50 lb and 1,500 kcal for 70 lb. Puppies, active dogs and intact dogs need more.
Is the feeding guide on the bag accurate?
It is a broad range for an average dog, often on the generous side. Many pet dogs need 10% to 20% less, especially if they are neutered or not very active.
How much should I feed my dog to lose weight?
Feed about the resting energy requirement for the target weight, not the current weight, and weigh the dog every two weeks. Aim for about 1% to 2% of body weight lost per week, with your vet's guidance.
How much should a puppy eat?
Puppies under 4 months need about 3 times their RER, and older puppies about 2 times, split into 3 or 4 meals a day for young puppies.
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Last updated October 2026.