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Body composition calculator

BMI Calculator

Frequently asked questions

How is BMI calculated?
BMI = weight (kg) ÷ height (m)². With imperial inputs, use 703 × weight (lb) ÷ height (in)². This calculator follows common WHO adult category cutoffs.
Is BMI an accurate measure of body fat?
No. BMI is a population screening estimate from height and weight. It can misclassify muscular athletes and does not replace medical advice or direct body-fat measures.
Can children use this BMI calculator?
This page is for adults. Children and teens need age- and sex-specific BMI charts rather than adult WHO cutoffs.

How the formula works

Adult BMI is weight (kg) ÷ height (m)². With imperial inputs, the equivalent is 703 × weight (lb) ÷ height (in)². Categories shown here follow common WHO adult cutoffs: underweight below 18.5, normal 18.5–24.9, overweight 25–29.9, and obesity at 30+.

BMI is a population screening estimate, not a direct measure of body fat, muscle mass, or health. It can misclassify muscular athletes and does not replace medical advice. This page is for adults; children and teens need age- and sex-specific charts.

BMI calculator form

BMI calculator results

Estimated BMI
24.7

Normal weight. Approximate healthy weight for this height: 59.9 kg – 80.7 kg.

BMI category reference

Adult BMI categories (WHO)
CategoryBMI range
Underweight< 18.5
Normal weight18.5–24.9
Overweight25.0–29.9
Obesity class I30.0–34.9
Obesity class II35.0–39.9
Obesity class III40.0+