BMI Calculator

Calculate your Body Mass Index with a visual scale showing underweight, normal, overweight, and obese categories.

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1. Select metric (kg/cm) or imperial (lbs/ft-in) units. 2. Enter your body weight in the chosen unit. 3. Enter your height in centimeters or feet and inches. 4. View your BMI score and its category on the visual scale. 5. Read the health guidance for your BMI range.

About This Tool

Body Mass Index (BMI) is a widely used screening tool that estimates body fat based on your height and weight. While it does not measure body fat directly, BMI correlates with more direct measures of body composition and serves as a useful starting point for assessing weight-related health risks.

Our BMI Calculator provides instant results along with an interactive visual scale that clearly shows where you fall across standard categories - underweight, normal weight, overweight, and obese. The calculator supports both metric (kg/cm) and imperial (lbs/ft-in) units, making it accessible to users worldwide.

Keep in mind that BMI has limitations. It does not account for muscle mass, bone density, age, or sex differences. Athletes and highly muscular individuals may have a high BMI without excess body fat. Always consult a healthcare professional for a comprehensive assessment of your health.

Formula / How It Works

BMI = weight (kg) / height (m)^2. In imperial units: BMI = (weight (lbs) x 703) / height (in)^2.

Frequently Asked Questions

A healthy BMI falls between 18.5 and 24.9. Below 18.5 is considered underweight, 25 to 29.9 is overweight, and 30 or above is classified as obese. These ranges apply to adults aged 20 and older.
BMI is calculated by dividing your weight in kilograms by your height in meters squared. In imperial units, multiply your weight in pounds by 703, then divide by your height in inches squared.
BMI can be misleading for athletes and muscular individuals because it does not distinguish between muscle and fat. A bodybuilder may have a high BMI but very low body fat. For athletes, body fat percentage measurements are more informative.
Children and teens use a different BMI system called BMI-for-age, which compares their BMI against growth charts for their age and sex. The standard adult BMI categories do not apply to anyone under 20.
A high BMI is associated with increased risk of heart disease, type 2 diabetes, high blood pressure, certain cancers, sleep apnea, and joint problems. Reducing BMI through diet and exercise can significantly lower these risks.

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