How do I measure the rib cage?
Use a flexible measuring tape to measure the circumference of your cat's rib cage at the level of the 9th rib, which is typically right behind the front legs.
Cat BMI & BCS Calculator
Calculate your cat's Feline Body Mass Index (fBMI) and Body Condition Score (BCS) using standard veterinary measurements.
All Pet Care Tools
Body Condition
-- Status
fBMI --
Body Fat % --
BCS (1-9) --
Measurements must be accurate for a correct BMI calculation. If unsure, a visual BCS check is recommended.
Frequently Asked Questions
How do I measure the leg length?
Measure the lower back leg from the knee to the ankle while the cat is standing.
What is BCS?
The Body Condition Score (BCS) is a standardized 1-9 scale used by veterinarians to assess whether a pet is too thin, ideal, or too heavy.
This site provides estimates and planning tools only. It does not replace veterinary advice, diagnosis, or treatment.