BMI Calculator
Calculate your Body Mass Index (BMI) instantly. Supports metric and imperial units with visual category indicator.
This calculator is for informational purposes only and should not replace professional medical advice.
How It Works
Metric formula: BMI = weight (kg) / height (m)²
Imperial formula: BMI = (weight (lbs) × 703) / height (in)²
Enter your weight and height, choose your preferred unit system, and your BMI will be calculated instantly along with a color-coded category indicator.
Frequently Asked Questions
What is BMI?
Body Mass Index (BMI) is a measure of body fat based on your weight relative to your height. It applies to adult men and women and is widely used as a simple screening tool for weight categories.
How is BMI calculated?
BMI is calculated by dividing your weight in kilograms by the square of your height in meters. In imperial units, the formula is (weight in pounds × 703) / (height in inches)².
What are the BMI categories?
Underweight: below 18.5, Normal weight: 18.5–24.9, Overweight: 25–29.9, Obese: 30 and above.
Is BMI accurate for everyone?
BMI does not distinguish between muscle and fat mass. Athletes or muscular individuals may have a high BMI without excess body fat. It's best used alongside other health measures.