BMI Calculator
Calculate your Body Mass Index (BMI) instantly. Supports both metric and imperial units with detailed category breakdown.
How to Use
- Choose your unit system by clicking either "Metric (kg/cm)" or "Imperial (lbs/ft)" at the top of the calculator.
- Enter your weight in kilograms (or pounds) and your height in centimeters (or feet/inches for imperial).
- Click "Calculate BMI" to see your BMI value, category, and position on the BMI scale.
- Review your results — the colored scale shows where you fall among the BMI categories from underweight to obese.
What is BMI and how is it calculated?
BMI (Body Mass Index) is calculated as weight in kilograms divided by height in meters squared. For imperial, it's (weight in lbs / (height in inches)²) × 703. It provides a general indication of body weight relative to height.
Is BMI an accurate measure of health?
BMI is a screening tool but doesn't account for muscle mass, bone density, age, or sex. Athletes may have high BMI due to muscle, while elderly may have low BMI with health issues. Use it as a general guide, not a diagnosis.
What are the BMI categories?
Underweight: below 18.5 | Normal: 18.5-24.9 | Overweight: 25-29.9 | Obese: 30 and above. Note that Asian populations may have different thresholds due to health risk differences.