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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: 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.
Details: BMI is a simple, inexpensive, and noninvasive surrogate measure of body fat. While it doesn't measure body fat directly, research has shown that BMI correlates to more direct measures of body fat. It is used as a screening tool to identify possible weight problems in adults.
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 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 be accurate for athletes (who may have high muscle mass), the elderly (who may have lost muscle mass), pregnant women, and children.
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: 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.
Q5: Should BMI be the only measure of health?
A: No, BMI should be used as a screening tool, not a diagnostic of body fatness or health. Other factors like waist circumference, diet, physical activity, and family history should also be considered.