What is a healthy BMI range?

According to the World Health Organization, a healthy BMI falls between 18.5 and 24.9. Values below 18.5 are classified as underweight, while values of 25 and above indicate overweight or obesity.

Is BMI accurate for athletes?

BMI does not distinguish between muscle mass and fat mass. Athletes with significant muscle may register as overweight or obese despite having low body fat. For a more complete picture, consider complementary measures like waist circumference or body fat percentage.

Does BMI differ for men and women?

The standard BMI formula and WHO category thresholds are the same for adult men and women. However, women typically have a higher body fat percentage at the same BMI compared to men, so context matters when interpreting the result.

Can I use BMI for children?

Children and teenagers use age- and sex-specific BMI percentile charts rather than the adult thresholds. A paediatrician can help interpret a child's BMI correctly using CDC or WHO growth charts.

How often should I check my BMI?

For most adults, checking BMI once every few months is sufficient. If you are actively trying to gain or lose weight, monthly checks can help you track progress, but daily fluctuations in weight make more frequent checks unreliable.

HEAHealth & Fitness

BMI Calculator

Calculate your Body Mass Index (BMI) instantly. Enter your weight and height to find out whether you fall into the underweight, normal, overweight, or obese category according to WHO standards.

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How It Works

Formula

\text{BMI} = \frac{m}{h^{2}}

Where

$\text{BMI}$: Body Mass Index(kg/m²)
$m$: Body weight(kg)
$h$: Height(m)

BMI is calculated by dividing your body weight in kilograms by the square of your height in metres. The resulting number is compared against WHO-defined ranges to classify your weight status. While BMI is a useful screening tool, it does not directly measure body fat or account for factors like age, sex, ethnicity, or muscle mass.

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