BMI Calculator
Calculate your Body Mass Index instantly with WHO classification.
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Frequently asked questions
What is BMI and how is it calculated?⌄
BMI = weight(kg) / height(m)². Based on height and weight, it estimates body fat. Example: 70 kg, 1.75 m → BMI 22.9.
What do the BMI categories mean?⌄
WHO: Underweight <18.5, Normal 18.5–24.9, Overweight 25–29.9, Obese I 30–34.9, Obese II+ 35+. For adults 20+.
Is BMI accurate for everyone?⌄
BMI is a screening tool, not a direct body fat measure. It may overestimate in athletes and underestimate in older adults. Consult a healthcare professional.
Does this calculator work for children?⌄
WHO categories here are for adults 20+. Children/teens need age- and sex-specific percentiles. This calculator may not be accurate for anyone under 20.
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