BMI Calculator (Body Mass Index)

BMI & BMI Prime Calculator

Enter height & weight, or edit BMI / BMI Prime—everything stays in sync.

Sex

Female Male

Height

Weight

BMI kg/m²

BMI Prime BMI ÷ 25

BMI

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BMI Prime

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BMI = weight (kg) ÷ height² (m²). WHO adult classification: <18.5 underweight; 18.5–<25 normal; 25–<30 overweight; ≥30 obesity (Class I: 30–<35; Class II: 35–<40; Class III: ≥40).
BMI Prime = BMI ÷ 25 (relative to the upper boundary of the normal range).
Note: BMI is a screening tool; body composition, pregnancy, and other factors can affect interpretation.

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