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BMI Formula:
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Body Mass Index (BMI) is a value derived from the mass (weight) and height of a person. It provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.
The calculator uses the following formulas:
Where:
Explanation: The formula first converts height from centimeters to feet, then calculates BMI using the standard formula for pounds and feet, with the 703 conversion factor to account for the units.
Details: BMI is a simple screening tool that can indicate whether a person is underweight, normal weight, overweight, or obese. While it doesn't measure body fat directly, research has shown that BMI correlates to direct measures of body fat.
Tips: Enter weight in pounds (lbs) and height in centimeters (cm). All values must be valid (weight > 0, height > 0). For most accurate results, measure height without shoes and weight with minimal clothing.
Q1: What are the standard BMI categories?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), Obesity (≥30).
Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and those with muscular build, and underestimate it in older persons who have lost muscle mass.
Q3: Why use this calculator instead of standard BMI calculators?
A: This calculator allows you to input height in centimeters while using weight in pounds, which can be convenient for those who prefer different measurement systems.
Q4: What are the limitations of BMI?
A: BMI doesn't account for muscle mass, bone density, overall body composition, or racial and sex differences.
Q5: Should BMI be the only measure of healthy weight?
A: No, other measures like waist circumference and body fat percentage should also be considered for a complete assessment.