BMI Formula:
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BMI (Body Mass Index) is a simple index of weight-for-height that is commonly used to classify underweight, normal weight, overweight and obesity in adults. It is calculated by dividing a person's weight in kilograms by the square of their height in meters.
The calculator uses the standard BMI formula:
Where:
Explanation: The formula provides a simple numeric measure of a person's "fatness" or "thinness" allowing health professionals to discuss overweight and underweight problems more objectively with their patients.
Details: BMI provides the most useful population-level measure of overweight and obesity as it is the same for both sexes and for all ages of adults. However, it should be considered a rough guide because it may not correspond to the same degree of fatness in different individuals.
Tips: Enter weight in kilograms and height in meters. For most accurate results, measure weight in the morning before eating and after using the bathroom. Measure height without shoes.
Q1: What are the standard BMI categories?
A: Underweight (BMI < 18.5), Normal weight (18.5-24.9), Overweight (25-29.9), and Obese (≥30).
Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and those with muscular builds, and underestimate it in older persons who have lost muscle mass.
Q3: How often should I check my BMI?
A: For most adults, checking every 6-12 months is sufficient unless you're actively trying to lose or gain weight.
Q4: Can children use this calculator?
A: Children and teens need age- and sex-specific BMI percentiles rather than the adult categories.
Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, but individual factors like muscle mass and body frame should be considered.