Calculate your Body Mass Index with metric or imperial units. See your BMI category, healthy weight range, and ideal weight instantly.
A BMI between 18.5 and 24.9 is considered normal weight for adults. Below 18.5 is underweight, 25–29.9 is overweight, and 30 or above is classified as obese by the WHO.
BMI for children (ages 2–19) is interpreted differently — it's compared against age and sex-specific percentiles rather than fixed cutoffs. This calculator uses adult BMI thresholds.
BMI is a screening tool, not a diagnostic one. It doesn't account for muscle mass, bone density, or fat distribution. Athletes may have a high BMI due to muscle, not fat. Always consult a healthcare professional for a full health assessment.