BMI Desirable Body Weight Calculator Body Mass Index ( BMI ) and Body Fat Percentage are validated measures of nutritional status. These are often used in clinical settings to see whether one is underweight, overweight or obese. BMI is based on the weight and height measurements and can be calculated by the following formula: BMI= Weight (kg)/ Height (m)2 BMI indicates whether body weight is proportional to body height. Please see the reference values for adult population: BMI Asian, Caribbean, African Caucasian Underweight <18.5 <18.5 Normal ...