What BMI tells you (and what it doesn't)
Body Mass Index is weight (kg) divided by height squared (m²). It's a quick population-level screening number: under 18.5 is underweight, 18.5–24.9 normal, 25–29.9 overweight, 30+ obese. It does not distinguish muscle from fat — athletes often score "overweight" while lean. Treat it as a starting point, not a diagnosis, and consult a professional for personal health decisions.