Diet feeding starts from the goal weight
Running the numbers on the current weight returns the calories that keep the current excess in place. This calculator instead takes the resting energy requirement of the target weight, multiplies it by a weight-loss factor for the daily calorie allowance, and divides by the label energy to give cups per day.
The resting energy requirement is RER = 70 × weight in kg^0.75, the formula AAHA and WSAVA both use, so pounds entered here are converted to kilograms before the exponent is applied. Loss factors differ slightly between sources, so 1.0 for dogs and 0.8 for cats are offered with a field for the figure your veterinarian gave you. Current as of October 2026.
No recommended weekly loss rate is supplied. Weekly loss is a flat percentage of the current weight, so the real pace slows as the weight falls. This tool is for reference only and does not replace veterinary care. Contact your veterinarian right away if you notice symptoms or suspect a problem.
Frequently asked questions
Calculating from the current weight returns the calories that maintain the current excess. Weight-loss feeding is built on the resting energy the target weight needs.
This tool suggests no rate. Safe loss depends on body condition, illness and age, so enter the figure your veterinarian set.
Weekly loss is a flat percentage of the current weight, so the pace slows as the weight drops. Re-weigh every two weeks and enter the new numbers.