BMI for men and women: is it calculated differently?
Learn why the adult BMI formula and categories are the same for men and women, while body composition may differ.
BMI uses the same adult formula regardless of sex:
BMI = weight (kg) / height (m)^2The standard adult categories are also the same for men and women. Sex does not change the arithmetic.
Interpretation can still differ at the individual level. People with the same BMI may have different proportions of fat and lean tissue or different fat distribution. Age, training history, menopause, medication use and medical conditions can also affect the broader picture.
Pregnancy is a special case: current pregnancy weight is not assessed through ordinary adult BMI categories. Clinicians use pre-pregnancy BMI and pregnancy-specific weight-gain guidance.
Use the BMI calculator as a screening tool, then consider waist measurement, body composition, blood pressure, laboratory markers and fitness when relevant. BMI alone cannot establish whether a particular man or woman has excess body fat or is healthy.