Feed smarter—with science, not guesswork.

Canned pet food labels often provide one-size-fits-all feeding instructions. But your dog or cat isn’t average. They have their own metabolism, weight, and energy needs. This calculator was created to give you a more accurate, science-based estimate of how much moisture-rich food to feed each day.

It’s built on veterinary nutrition formulas—not marketing spin—so you can make informed decisions that support real health, not just label claims.

Enter your pet’s current weight in pounds. Use decimals for accuracy (e.g., 12.5 lbs). The calculator will convert this to kilograms and use a standard veterinary formula to determine your pet’s Resting Energy Requirement (RER)—the number of calories they need each day at rest, just to fuel basic functions like breathing, circulation, digestion, and repair.

RER = 70 × (body weight in kg)^0.75
This formula is recognized by the NRC, AAFCO, WSAVA, and veterinary nutrition experts worldwide.

After calculating RER, the tool multiplies it by a science-backed factor to estimate your pet’s Maintenance Energy Requirement (MER)—the calories they need based on activity, metabolism, reproductive status, and life stage.

Life Stage or ConditionMultiplier (× RER)Neutered Adult Dog or Cat1.6Intact Adult Dog1.8Intact Adult Cat1.4Inactive / Obese-Prone Pet1.1–1.2Senior Dog or Cat1.4Active / Working Dog2.0–5.0Puppy (0–4 months)3.0Puppy (4–12 months)2.0Giant Breed Puppy (>25kg adult)1.8Kitten (Under 4 Months)2.5Kitten (4–12 Months)2.0Weight Loss (Use Ideal Weight)1.0 

Not sure which to choose? “Neutered Adult” is a safe starting point. Ask for help if you’re unsure.
 

This calculator uses the calories per can and the weight of the can (in grams) to determine how much food your pet needs each day in practical terms—like grams, ounces, and cans.

• Calories per Can (kcal): Look for this on your can’s label (e.g., 81 kcal)
   
• Weight per Can (grams): This is usually printed on the front or side of the can (e.g., 85g, 156g, 368g)
   

If you're unsure where to find this info, stop by the store—I’ll help you look it up.

After entering your pet’s details and can information, the calculator provides:

• Calories per day your pet needs (MER)
   
• Cans per day to meet those needs
   
• Feeding in grams and ounces
   
• A suggested number of meals per day
   
• The treat calorie limit (based on the 10% rule)
   

This is the same method used in veterinary nutrition programs, applied in a way that’s simple and practical.

Calories from treats, chews, table scraps, supplements, and toppers all contribute to your pet’s daily total. Even “healthy” extras can unbalance a feeding plan.

As a general rule:

• Treats should not exceed 10% of your pet’s daily calories
   
• If your dog needs 550 kcal/day, treats should be limited to about 55 kcal or less
   
• For cats or small dogs with low needs, even one biscuit can make a big difference
   

Be aware of how chews, dental sticks, or extra bites impact the day’s total intake. It adds up.

Want help choosing low-calorie treats that support your feeding plan? I’ll help you pick options that match your goals.

If your pet’s calorie requirement is below 200 kcal/day, there may be a nutrient risk—especially for small dogs and cats or pets on weight-loss plans.

Here’s why:

• Most commercial foods are formulated to meet essential nutrients per 1000 kcal
   
• Feeding much less than that means your pet may not receive enough protein, vitamins, taurine, or minerals to meet their daily needs
   

This risk increases when:

• Using small portions of regular canned food
   
• Feeding for weight loss without professional support
   
• Feeding only one brand or flavor over time
   

If this applies to your pet:

• Use their ideal weight for calculations
   
• Choose high-protein, low-carbohydrate formulas
   
• Monitor body condition—not just the scale
   
• Consult with a veterinary nutritionist, or stop by and I’ll help you navigate it safely
   

This tool is designed for:

• Healthy adult dogs and cats
   
• Eating canned/moisture-rich food only
   
• Having normal daily activity levels
   

This tool is not intended for:

• Pets eating dry, freeze-dried, raw, or home-cooked food
   
• Animals on prescription diets or managing health conditions (e.g. kidney disease, pancreatitis, diabetes)
   
• Pregnant, nursing, or geriatric pets needing medical support
   
• Pets undergoing therapeutic weight loss or gain without a tailored plan
   
• Young kittens or puppies needing phase-based nutrition
   

This calculator is built on the same formulas taught in veterinary education and used by clinical nutritionists:

• Resting Energy Requirement (RER): 70 × (body weight in kg)^0.75
   
• Maintenance Energy Requirement (MER): RER × species-specific multiplier
   
• Sourced from:
   
  • Canine and Feline Nutrition (Case, Daristotle, Hayek, Raasch)
     
  • NRC Nutrient Requirements for Dogs and Cats
     
  • WSAVA Global Nutrition Toolkit
     
  • Peer-reviewed clinical nutrition publications
     

It reflects how pets use energy—not what manufacturers want you to buy.

This tool was developed by Purrs McBarkin’, LLC, an independent pet supply store in Hartsville, South Carolina.

I’m Dave Zanoni, Certified Canine and Feline Nutritionist. I built this tool to give pet parents honest, science-backed guidance to support feeding decisions—without fluff, fear, or sales pressure.

Need help reading your label or understanding a feeding plan? Stop by the store or reach out—I’m here to help.

This calculator is for educational purposes only and does not constitute medical advice. Feeding estimates are based on standard veterinary nutrition calculations and assume normal health status.

Always consult your veterinarian before making changes to your pet’s diet—especially if your pet has a medical condition, is on a prescription plan, or has unique dietary needs.

Use of this tool is voluntary and at your own discretion.

This calculator and all related content are the exclusive property of Purrs McBarkin’, LLC.
Reproduction, modification, or commercial use without written permission is strictly prohibited.

© 2025 Purrs McBarkin’, LLC. All rights reserved.