Veterinary energy & feeding calculator
One place for dog and cat RER, source-reviewed energy estimates, food amounts, weight-loss planning, and cautious hospitalized-patient progression.
Clinical Goal
Choose a goal, then enter weight
Safety checks
- Calculation basis: this tool converts entered weight, species, mode, and optional food density into a structured starting energy estimate.
- Scope: it helps with calorie arithmetic and progression planning. It does not choose the therapeutic diet, disease-specific target, or final medical nutrition strategy.
- Before acting: compare the estimate with body condition, hydration status, current intake, and the patient’s response over time.
- Hospitalized patients: reassess tolerance, electrolytes, and clinical trajectory rather than treating the progression output as an autopilot protocol. Feeding route and clinical-context fields document the case; they do not select treatment.
Basis and limits
RER formula: RER = 70 × (body weight in kg)^0.75. The constants are fixed to the reviewed AAHA calculation basis.
Adult profiles use AAHA species-specific factor ranges: neutered dogs 1.4–1.6, intact dogs 1.6–1.8, neutered cats 1.2–1.4, and intact cats 1.4–1.6. Weight-loss estimates use estimated ideal weight; the hospital mode starts at 25% RER and steps toward 100% over about four days, subject to patient tolerance.
The maintenance pathway also includes AAHA life-stage factors for growth, gestation, lactation, inactive adults, and working dogs. Where AAHA gives a broad range rather than one fixed factor, this tool shows the energy range and requires a clinician-reviewed factor before it displays one daily target or food amount. There is no universal senior multiplier, so senior patients start from an adult range and need reassessment.
References: AAHA 2021 Nutrition and Weight Management Guidelines and Purina Institute hospital-feeding guidance. Verify patient-specific decisions with current references and a veterinarian.
Math you can verify
Enter a current body weight to see the RER calculation and selected energy-factor path.
Owner Summary
Feeding instructions
Last reviewed: May 2026
References: Plumb's Veterinary Drug Handbook, Merck Veterinary Manual, BSAVA Formulary, AAHA Guidelines. Verify against current references before clinical use.