Dog Food Calculator

Use this dog food calculator to estimate how much to feed my dog every day, expressed in calories (kcal) and in grams of food. It applies the same resting-energy-requirement (RER) and maintenance-energy-requirement (MER) method that veterinary nutritionists and WSAVA guidelines use during nutrition consults.

Enter your pet’s species, body weight and life stage, and — optionally — the energy density printed on the bag to turn the result into a daily ration. This dog calorie calculator gives a transparent starting point: always fine-tune to body condition and confirm with your veterinarian.

Enter a valid body weight to see the daily calorie and food estimate.

This is a starting estimate, not a prescription. Adjust to your pet’s body condition score and weight trend, and consult your veterinarian before changing the diet — especially for puppies, pregnant or lactating animals, or pets with a medical condition.

How the dog food calculator works

Daily energy needs are built in two steps. First we compute the resting energy requirement (RER) — the calories an animal burns at rest. Then we multiply it by a maintenance-energy factor (MER) that reflects life stage, neuter status and activity.

RER formula used by the dog food calculator
RER = 70 × (body weight in kg) ^ 0.75MER = RER × life-stage factorGrams per day = MER ÷ (kcal per 100 g ÷ 100)
MER factors used in this dog calorie calculator
SpeciesLife stage / activityMER factor
DogAdult — weight loss×1.0
DogNeutered adult×1.6
DogIntact adult×1.8
DogSenior×1.4
DogActive / working×3.0
DogPuppy (0–4 months)×3.0
DogPuppy (4–12 months)×2.0
CatAdult — weight loss×0.8
CatNeutered adult×1.2
CatIntact adult×1.4
CatSenior×1.1
CatActive×1.6
CatKitten×2.5

Frequently asked questions

How many calories does my dog need per day?

A dog’s daily calories equal its resting energy requirement (RER = 70 × weight in kg^0.75) multiplied by a maintenance factor for its life stage. A neutered 12 kg adult dog (factor 1.6), for example, needs roughly 720 kcal per day. Use the calculator above for your dog’s exact figure.

How much should I feed my dog in grams?

Divide the daily calorie target by the food’s energy density. If your dog needs 720 kcal and the kibble provides 350 kcal per 100 g, the daily ration is 720 ÷ 3.5 ≈ 206 g. Enter the kcal per 100 g from the bag and the calculator returns grams automatically.

What is RER and MER?

RER (resting energy requirement) is the energy a pet burns at complete rest. MER (maintenance energy requirement) is RER multiplied by a factor for activity, life stage and neuter status, and represents the total daily energy the pet actually needs.

Does a neutered dog need fewer calories?

Yes. Neutering lowers metabolic rate, so a neutered adult dog uses a factor of about 1.6 versus 1.8 for an intact adult — roughly 10–15% fewer calories. Adjusting portions after neutering helps prevent weight gain.

Is this dog food calculator accurate for puppies and seniors?

It uses standard WSAVA factors (3.0 for puppies under four months, 2.0 from four to twelve months, 1.4 for seniors), which are good starting points. Growing puppies and seniors need closer monitoring, so re-weigh regularly and adjust to body condition.

How often should I recalculate how much to feed my dog?

Re-check the ration whenever weight, activity or life stage changes, and at least every few months. Track body condition score and trend the weight; if your dog is gaining or losing unintentionally, adjust calories and consult your veterinarian.

Run nutrition consults in minutes, not spreadsheets

Veterical helps your clinic store every patient’s weight, body condition and diet plan in one place — so ration calculations stay consistent at every visit.