Cat BMI Calculator
Get a simplified body-mass-index style estimate for your cat based on weight and body length.
What This Calculator Does
This calculator gives a simplified body-mass-index style estimate for cats, using the same weight-to-length-squared approach as human BMI, adapted for a cat’s weight and body length.
The Formula
The calculation is BMI = Weight (kg) / Body length (m)², using body length measured from the nose to the base of the tail. There is no single universally standardized BMI scale for cats; veterinary body condition scoring (a hands-on 1-9 scale assessing rib coverage and waist shape) is the accepted clinical method for judging a cat’s weight status.
- Weigh your cat on a scale in kilograms.
- Measure body length in a straight line from the nose to where the tail begins.
Treat this number as a rough, general-reference estimate only, not a veterinary diagnosis. Ask your veterinarian for a proper body condition score assessment for an accurate picture of your cat’s weight health.