BMI & Body Composition Calculator
Compute Body Mass Index, body surface area, and ideal weights with responsive metric/imperial conversions.
Biometric Profiles
kg
20 kg250 kg
cm
90 cm240 cm
Body Analysis
Your Body Mass Index
24.2
Normal
Healthy Weight Range
53.5
53.5 - 72 kg Formula Target Weight
65.9
65.9 kg (Devine Formula) Body Surface Area
1.82 m²
Total skin area Ponderal Index
14.2 kg/m³
Stature adjusted BMI What do these metrics mean?
- Body Surface Area (BSA): The calculated surface area of your body. Doctors use this instead of weight to determine precise medicine dosages.
- Ponderal Index: A version of BMI that is more accurate for very tall or very short people because it calculates weight against cubed height.
Understanding BMI & Body Metrics
Body Mass Index (BMI) is a simple estimate of body fatness based on height and weight. Our category classifications and ideal weight ranges follow the clinical standards defined by the World Health Organization (WHO) and the Centers for Disease Control and Prevention (CDC).
Mathematical Formula
\text{BMI} = \frac{\text{Weight (kg)}}{\text{Height (m)}^2}
\text{BSA (Mosteller)} = \sqrt{\frac{\text{Height (cm)} \times \text{Weight (kg)}}{3600}}
Formula Explanation:
- Underweight: BMI < 18.5 (WHO standard)
- Normal Weight: BMI 18.5 to 24.9 (WHO standard)
- Overweight: BMI 25 to 29.9 (WHO standard)
- Obese: BMI ≥ 30 (WHO standard)
- Ponderal Index: Normalized BMI metric adjusted for taller/shorter statures (kg/m³)
- Reference standard: Devine Ideal Weight formulas are clinical dosing standards.
Terms & Abbreviations
BMI Body Mass Index - ratio of body weight to squared height.
BSA Body Surface Area - measured total surface area of a human body.
Devine Formula Established medical algorithm to determine ideal body weight for drug dosages.
Frequently Asked Questions
No. BMI does not differentiate between lean muscle mass and fat mass. Extremely fit individuals or bodybuilders may register as Overweight or Obese despite having very low body fat.
BSA is widely used in clinical medicine to compute proper fluid requirements, chemotherapy drug dosages, and cardiac indices.
You can toggle the Metric / Imperial switch. The sliders will remain responsive, allowing you to view weights in pounds (lbs) and heights in feet/inches.
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