Free online tool

BMI Calculator

Convert height and weight into BMI and a reference weight range for that height.

Body mass index--
Reference weight range-BMI 18.5-24.9

Adult screening estimate only. It does not replace an individual medical or body-composition assessment.

Method

Health estimate method

BMI uses weight divided by height squared. Energy estimates use the Mifflin-St Jeor equation with the selected activity multiplier, while circumference-based body fat uses the US Navy field formula.

These population formulas are screening and planning estimates, not diagnoses or individual prescriptions. Age, body composition, measurement technique, health, and training can materially change interpretation.

Questions

BMI Calculator FAQ

How is BMI calculated?

BMI is weight in kilograms divided by height in meters squared.

Does BMI measure body fat directly?

No. BMI is a screening ratio and does not directly distinguish fat, muscle, bone, age, sex, or body composition.

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