BMI & Body Surface Area

Calculate BMI and BSA using DuBois and Mosteller formulas. Essential for drug dosing, metabolic assessment, and cardiac output indexing.

cm

Patient height in centimeters (30–300 cm)

kg

Patient weight in kilograms (1–500 kg)

Enter height and weight, then click Calculate

Clinical Notes

  • BMI < 18.5: Underweight — consider malnutrition screening.
  • BMI 18.5–24.9: Normal weight — lowest all-cause mortality range.
  • BMI 25–29.9: Overweight — lifestyle counseling recommended.
  • BMI 30–34.9: Obese Class I — weight management program.
  • BMI 35–39.9: Obese Class II — consider medical weight management.
  • BMI ≥ 40: Obese Class III — consider bariatric evaluation.

Note: BSA is used for chemotherapy dosing, cardiac index calculation (CI = CO/BSA), and IV fluid requirements. DuBois formula is most widely used; Mosteller is simpler and equally accurate at extremes of body size.