Pet Care Calculators
Dog Food Portion Calculator
Use this dog food portion calculator to estimate how much to feed your dog each day. It calculates daily calories from your dog's weight and life stage, then converts that into cups based on the calories in your specific food.
Last reviewed: June 2026
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Your result will appear here after you press Calculate.
Estimate only. Treats should make up no more than about 10% of daily calories. Re-check portions as your dog's weight changes.
Formula used
The calculator uses the standard veterinary energy formula:
- Resting Energy Requirement (RER) = 70 × (body weight in kg)^0.75
- Daily calories (MER) = RER × life-stage/activity factor
- Factors: neutered adult 1.6, intact 1.8, light activity 2.0, heavy 3.0, puppy 2.0–3.0, senior 1.4, weight loss 1.0
- Food per day = daily calories ÷ calories per cup
Worked examples
30 lb neutered adult dog, 350 kcal/cup food
A 30 lb (13.6 kg) dog has an RER of about 493 kcal. As a neutered adult (×1.6) that's roughly 790 kcal/day, or about 2.3 cups of a 350 kcal/cup food, ideally split into two meals.
60 lb active dog, 400 kcal/cup food
A 60 lb (27 kg) dog in light work needs about 1,660 kcal/day (×2.0), which is roughly 4.1 cups of a 400 kcal/cup food per day.
How to use this calculator
- Enter your dog's current weight and choose pounds or kilograms.
- Select the life stage or activity level that best matches your dog.
- Enter the calories per cup from your dog food bag (look for “kcal/cup”).
- Press Calculate to see the daily calories and cups, then split the amount into meals.
Reference chart
| Weight | RER (kcal) | Daily calories |
|---|---|---|
| 10 lb (4.5 kg) | 217 | ≈ 345 |
| 20 lb (9 kg) | 365 | ≈ 585 |
| 40 lb (18 kg) | 613 | ≈ 980 |
| 60 lb (27 kg) | 830 | ≈ 1,330 |
| 80 lb (36 kg) | 1,030 | ≈ 1,650 |
Frequently asked questions
How much food should I feed my dog per day?
It depends on your dog's weight, life stage, activity, and the calories in the food. This calculator estimates daily calories using the veterinary RER formula and an activity factor, then converts to cups using your food's kcal/cup. Always cross-check with the bag's feeding guide and your vet.
How do I find the calories in my dog food?
Look on the bag or the brand's website for a “Calorie Content” statement, usually given as kcal per cup (or kcal/kg). Dry foods commonly range from about 300 to 450 kcal per cup. Enter that number for an accurate portion.
Should I feed my dog once or twice a day?
Most adult dogs do best with two meals a day, split evenly. Puppies need more frequent meals — three to four times a day. Dividing the daily amount helps digestion and reduces begging and bloat risk in deep-chested breeds.
How is the calorie estimate calculated?
It uses Resting Energy Requirement (RER = 70 × kg^0.75) multiplied by a life-stage factor to get the Maintenance Energy Requirement (MER). This is the same approach veterinary nutritionists use, though individual dogs vary by 20% or more.
My dog is overweight — how much should I feed?
Choose the “Weight loss” option, which uses a lower factor based on ideal (target) body weight rather than current weight. For safe, supervised weight loss, work with your veterinarian, who can set a target weight and monitor progress.
Is this calculator a substitute for my vet?
No. It's an informational estimate to help you portion food sensibly. Your veterinarian can account for body condition score, health conditions, and your dog's response to feeding, and should guide diet changes.