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Pet Calorie Calculator

Calculates daily caloric needs using the Resting Energy Requirement (RER) formula vets use: RER = 70 × (body weight in kg)0.75. That baseline gets multiplied by a life-stage factor for your pet's actual maintenance calorie count.

Resting (RER)

895 cal

Daily target (MER)

1,074 cal

Formula: RER = 70 × (kg)0.75, MER = RER × life-stage factor (AAHA / WSAVA references). Real caloric needs vary by breed, body condition, and individual metabolism — adjust by ±15% based on Body Condition Score every 2-4 weeks.

Why food-bag charts overfeed

Most kibble feeding charts are calibrated for active, intact adult pets — but most U.S. pets are neutered indoor adults who need 20-30% fewer calories than the bag recommends. That explains the most common reason pets gain weight even when owners "feed the right amount."

Use this calculator's target, weigh portions for 2-4 weeks, then re-check Body Condition Score. If ribs are getting harder to feel: drop calories by 10%. If ribs are getting more prominent: increase by 10%. Repeat until stable at ideal BCS (4-5/9).

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Reviewed by Dr. Tiffany Delacruz, DVM — written for pet parents in Florida, New York, and Virginia.