BMI Formula:
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Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, overweight and obesity in adults. It is defined as a person's weight in kilograms divided by the square of their height in meters (kg/m²).
The calculator uses the BMI formula:
Where:
Explanation: The formula calculates body mass index by dividing weight by the square of height, providing a standardized measurement of body fatness.
Details: BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients. It is used to screen for weight categories that may lead to health problems.
Tips: Enter weight in kilograms and height in meters. For accurate results, measure weight without heavy clothing and height without shoes. All values must be valid (weight > 0, height > 0).
                    Q1: What are the standard BMI categories?
                    A: Underweight: BMI < 18.5; Normal weight: BMI 18.5-24.9; Overweight: BMI 25-29.9; Obesity: BMI ≥ 30.
                
                    Q2: Is BMI accurate for everyone?
                    A: BMI may not accurately reflect body fatness in athletes (who may have high muscle mass), the elderly (who may have lost muscle mass), or certain ethnic groups.
                
                    Q3: How often should I check my BMI?
                    A: For most adults, checking BMI annually is sufficient unless you're actively trying to lose or gain weight.
                
                    Q4: Can children use this calculator?
                    A: This calculator is designed for adults. Children and teens require age and sex-specific percentiles for accurate assessment.
                
                    Q5: What's a healthy BMI range?
                    A: For most adults, a BMI between 18.5 and 24.9 is considered healthy and associated with the lowest health risks.