Calculators

BMI Calculator

Calculate your body mass index (BMI) in imperial or metric units, see your BMI category and the healthy weight range for your height.

lb
ft
in
kg
cm

Enter your values and press Calculate.

How to use the BMI calculator

BMI is a quick screening measure, not a diagnosis. It does not distinguish muscle from fat, so very muscular people can score as “overweight”. It also is not designed for children, pregnant people or older adults. Speak to a doctor about what is healthy for you.

Formula

BMI = weight (kg) ÷ height (m)², or 703 × weight (lb) ÷ height (in)².

Adult categories: under 18.5 underweight, 18.5–24.9 healthy, 25–29.9 overweight, 30+ obese.

Frequently asked questions

Is BMI accurate?

BMI is a useful population-level indicator but can misclassify individuals, especially athletes. Waist measurement and body fat percentage add useful context.

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