Dog Food Calculator by Weight & Calories | Sullpet

Pet Food Calculator for Dogs and Cats

Estimate your pet's daily calorie needs and convert that estimate into food portions using the calorie information on your own food package. Results are starting estimates, not a veterinary prescription.

Pet type Dog Cat

Life stage / status Adult dog — neutered Adult dog — not neutered Adult dog — prone to weight gain Puppy — under 4 months Puppy — 4 months or older Adult cat — neutered Adult cat — not neutered Adult cat — prone to weight gain Kitten — growing

Choose the option that best fits your pet.

Current body weight

Weight unit Kilograms (kg) Pounds (lb)

Food energy (kcal per cup)

Find kcal/cup on your food label. Enter the value for the food you actually feed.

Food weight (grams per cup)

Optional. Use the package value if available; cups vary by food.

Meals per day 1 meal 2 meals 3 meals 4 meals

How does the pet food calculator work?

The calculator estimates resting energy requirement (RER) using body weight in kilograms. It then applies a general life-stage factor to estimate daily maintenance energy needs.

Resting energy requirement:

RER = 70 × (body weight in kg)^0.75

Estimated daily energy:

Daily kcal = RER × life-stage factor

Convert calories to food:

Food cups per day = daily kcal ÷ kcal per cup

If you enter grams per cup, the calculator also estimates grams per day. The value depends on your particular food's calorie density and cup weight.

Frequently asked questions

How much food should I feed my dog each day?

It depends on body weight, life stage, activity, health and the calorie density of the food. Use the calculator as a starting estimate and confirm portions with your food label and veterinarian.

How do I calculate dry dog food in grams?

Enter kcal per cup and, if the label or manufacturer provides it, grams per cup. The calculator converts the estimated cups into grams. Weighing food on a kitchen scale is often more consistent than measuring by volume.

Can I use this calculator for cats?

Yes, for a general estimate for healthy adult cats and growing kittens. Cats with medical conditions, weight concerns, pregnancy or other special needs require individual guidance.

Are the results exact?

No. Energy requirements vary between individual animals, including pets of the same weight. Monitor body condition and weight, and seek veterinary advice before making significant dietary changes.

Calculation source

The general RER equation and life-stage factors are based on published veterinary nutrition references. They are intended as starting estimates and not as a diagnosis or treatment plan.

Merck Veterinary Manual: Daily Maintenance Energy Requirements for Dogs and Cats