BMI Calculator — Metric (kg, cm)
The metric BMI page works in kilograms and centimeters, the units used across most of the world and in clinical practice. It applies the original formula BMI = kg / m², dividing your height in centimeters by 100 to get meters before squaring it. Enter a weight in kilograms and a height in centimeters to see your index, your WHO category, and the kilogram weight band that keeps BMI between 18.5 and 24.9 for your height.
Body mass index estimate
Estimated BMI
22.9
Normal weight
Reference for your height
Healthy weight band (kg) for BMI 18.5–24.9 at the height entered.
BMI = kg / m², classified against the WHO adult categories. It is a screening estimate that ignores muscle, frame, age, and sex — not a medical diagnosis or dietary advice. Consult a healthcare professional before acting on this number.
Working in kilograms and centimeters
The metric page uses the original definition of the index, BMI = kg / m². You enter weight in kilograms and height in centimeters; the tool divides the height by 100 to convert it to meters, squares that, and divides your weight by the result. These are the units used across most of the world and in clinical practice, so no conversion factor is needed.
The index it produces is identical to the imperial page — only the input units differ. The result is a screening estimate that places you in a WHO category and shows a healthy kilogram band for your height, not a measure of body fat or a diagnosis.
Questions
- What is the metric BMI formula?
- BMI = kg / m². The tool divides your height in centimeters by 100 to get meters, squares it, then divides your weight in kilograms by that value. No 703 factor is needed because the inputs are already metric.
- Do metric and imperial give the same BMI?
- Yes. The index and its WHO category are identical regardless of the units you enter; only the input fields differ. The imperial page applies a 703 factor purely to convert pounds and inches into the same metric ratio.
More ways to use this calculator
Start with the main bmi calculator or compare the other published scenarios.
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