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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 BMI formula:
Where:
Explanation: The formula provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems 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 body fat percentage in different individuals.
Tips: Enter weight in kilograms and height in meters. For height, you can convert from cm to m by dividing by 100 (e.g., 175 cm = 1.75 m). All values must be valid (weight > 0, height > 0).
Q1: What is a healthy BMI range?
A: For most adults, an ideal BMI is in the 18.5 to 24.9 range. Below 18.5 is underweight, 25-29.9 is overweight, and 30 or above is obese.
Q2: Does BMI apply to everyone?
A: BMI may not be accurate for athletes (who may have high muscle mass), pregnant women, the elderly, or children (who need age-specific charts).
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: 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 certain ethnic groups or body types.
Q5: Should BMI be the only measure of healthy weight?
A: No, waist circumference and other health markers should also be considered for a complete health assessment.