What's the BMI formula?

Metric: weight(kg) ÷ height(m)². Imperial: 703 × weight(lb) ÷ height(in)².

What BMI ranges do you use?

Underweight < 18.5, Normal 18.5–24.9, Overweight 25–29.9, Obese ≥ 30. These are WHO adult thresholds.

Does BMI work for athletes?

BMI doesn't distinguish muscle from fat, so very muscular people can show as overweight without being unhealthy. It's a screening tool, not a diagnosis.

Is BMI suitable for children?

Children use percentile-based BMI-for-age charts. This tool uses the adult formula.

Are my measurements stored?

No — the calculation happens entirely in your browser. Nothing is uploaded.

BMI Calculator

Q: What BMI ranges do you use?

Underweight < 18.5, Normal 18.5–24.9, Overweight 25–29.9, Obese ≥ 30. These are WHO adult thresholds.

Q: Does BMI work for athletes?

BMI doesn't distinguish muscle from fat, so very muscular people can show as overweight without being unhealthy. It's a screening tool, not a diagnosis.