Body Mass Index is a measure of body fat based on your height and weight. It's calculated as weight (kg) ÷ height² (m²).

What is a healthy BMI range?

A BMI of 18.5–24.9 is considered normal weight. Under 18.5 is underweight, 25–29.9 is overweight, and 30+ is obese.

Is BMI accurate for athletes?

BMI doesn't distinguish between muscle and fat. Athletes with high muscle mass may show as 'overweight' despite being healthy.

This calculator is designed for adults 18+. Children's BMI uses age-specific percentile charts.

Calculate your Body Mass Index and health category. Instant, accurate, free.

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Weight (kg)

Height (cm)

Underweight

< 18.5

Normal

18.5 – 24.9

Overweight

25 – 29.9

Obese

≥ 30

How useful is BMI Calculator?

Enter your height in cm or feet/inches

Enter your weight in kg or pounds

Click "Calculate" to see your BMI score

Read your health category — underweight, normal, overweight, or obese

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