BMI Calculator – Free Body Mass Index Check | Zen Hub
BMI (Body Mass Index) divides your weight in kilograms by your height in meters squared. The WHO classifies adults as underweight (<18.5), normal (18.5–24.9), overweight (25–29.9), or obese (≥30). BMI is a useful general screening tool but does not differentiate muscle from fat — see our athlete BMI variant for context.
Last updated: May 2026
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