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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 measure 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. All values must be valid (weight > 0, height > 0). For accurate results, measure weight without heavy clothing and height without shoes.
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: Can BMI be used for children?
A: BMI is calculated the same way for children but interpreted differently, using age and sex-specific percentile charts rather than fixed categories.
Q4: What are the limitations of BMI?
A: BMI doesn't distinguish between muscle and fat, doesn't account for fat distribution, and may not be accurate for very tall or short individuals.
Q5: Should BMI be the only measure of healthy weight?
A: No, BMI should be used as a screening tool alongside other measurements like waist circumference, body composition analysis, and overall health assessment.