How to calculate BMI?

Body Mass Index (BMI) is calculated by dividing a person's weight by the square of their height. It is a screening tool used to categorize weight status (underweight, healthy weight, overweight, or obesity). There are different formulas for metric (kg/m²) and imperial (lbs/in²) systems.

Formula

Metric: BMI = Weight (kg) ÷ (Height (m))² Imperial: BMI = (Weight (lbs) ÷ (Height (in))²) × 703

Worked Example (Metric)

Weight: 70 kg, Height: 1.75 m.

  1. Square Height: 1.75 × 1.75 = 3.0625
  2. Divide Weight: 70 ÷ 3.0625 = 22.86

Result: The BMI is 22.86 (Healthy Weight).

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