Free Pet Nutrition Tool

Dog & Cat Feeding Calculator

Enter your pet's weight, age, and lifestyle to instantly calculate their daily calorie needs and exact food portions — using the same RER formula used by vets.

Calculate My Pet's Portions ↓

Enter your pet's details

I have a...
Basic info

Tell us about your pet so we can calculate their unique calorie needs.

Enter age in months (1–240)
Food details

Enter what you feed your pet so we can convert calories into real portion sizes.

Check your pet food packaging
Fill in the details above and hit Calculate

How the calculator works

Based on the RER (Resting Energy Requirement) formula used by veterinary nutritionists worldwide.

1

Enter pet details

Weight, age in months, activity level, body condition, and neuter status.

2

RER calculated

We compute Resting Energy Requirement: 70 × (weight kg)^0.75.

3

Multipliers applied

Age, activity, neuter status, and body condition multipliers adjust the base number.

4

Portions shown

Daily kcal needs are converted to cups, grams, or a mixed split based on your food type.

From the blog

Pet nutrition guides to help you feed your dog or cat with confidence.

Dog Nutrition

How Much Should You Feed Your Dog? A Complete Guide

Everything you need to know about calculating your dog's daily food portions — from puppies to seniors.

6 min read · Dog Care
Cat Nutrition

How Much Should You Feed Your Cat? Vet-Approved Guide

Kittens, adults, seniors — find out exactly how much food your cat needs each day and why getting it right matters.

5 min read · Cat Care
vs
Pet Food

Dry vs Wet Pet Food: Which Is Better for Your Pet?

Comparing kibble and wet food on nutrition, cost, convenience, and how each affects your pet's daily calorie portions.

5 min read · Pet Nutrition

Frequently asked questions

Common questions about pet feeding and how our calculator works.

How much should I feed my dog per day?
The amount depends on your dog's weight, age, activity level, and whether they are neutered. Use our calculator above — it applies the veterinary RER formula and adjusts for your dog's specific profile to give you a daily kcal target and cup or gram recommendations.
How do I calculate my cat's daily food portion?
Cats have different caloric multipliers than dogs. Our calculator uses the standard RER formula and applies cat-specific multipliers based on age (kitten vs adult vs senior), neuter status, and body condition to give accurate daily portion sizes.
What is RER in pet nutrition?
RER stands for Resting Energy Requirement — the number of calories a pet needs at complete rest to maintain basic body functions. It is calculated as 70 × (body weight in kg)^0.75. Daily energy needs are then calculated by multiplying this base number by a life-stage multiplier.
Should I feed my puppy differently than an adult dog?
Yes. Puppies need significantly more calories relative to their size — up to 3× RER for very young puppies (0–4 months) and 2× RER for puppies aged 4–12 months. Our calculator automatically applies the correct multiplier based on the age in months you enter.
Is this calculator suitable for all dog and cat breeds?
The calculator uses universal veterinary formulas that apply to all breeds. However, some breeds have breed-specific metabolic differences. Always use the result as a starting point and monitor your pet's weight and body condition over time. Consult your vet for personalised advice.
Where do I find the calorie content of my pet food?
Check the back of your pet food packaging. Dry food is usually listed as kcal per cup or kcal per kg. Wet food is usually kcal per 100g or kcal per tin. Many manufacturers also list this information on their websites.