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BMI Formula:
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Body Mass Index (BMI) is a value derived from an individual's weight and height. It provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems objectively with their patients.
The calculator uses the standard BMI formula:
Where:
Explanation: The formula converts height to total inches, squares it, divides weight by this value, then applies the conversion factor to get the standard BMI measurement.
Details: BMI is widely used as a screening tool to identify possible weight problems in adults. While it doesn't measure body fat directly, research has shown that BMI correlates to direct measures of body fat.
Tips: Enter your weight in pounds, height in feet and inches. All values must be valid (weight > 0, height > 0). For most accurate results, measure your height without shoes and weight with minimal clothing.
Q1: What is a healthy BMI range?
A: For adults, 18.5-24.9 is considered normal weight, 25-29.9 overweight, and 30+ obese. However, these ranges may vary by ethnicity and other factors.
Q2: Are there limitations to BMI?
A: Yes. BMI doesn't distinguish between muscle and fat, so athletes may have high BMI without excess fat. It also may not be accurate for pregnant women, the elderly, or certain ethnic groups.
Q3: Is BMI different for children?
A: Yes. For children and teens, BMI is age- and sex-specific and is referred to as BMI-for-age. This calculator is for adults only.
Q4: How often should I check my BMI?
A: For most adults, checking every few months is sufficient unless you're actively trying to lose or gain weight.
Q5: What should I do if my BMI is outside the normal range?
A: Consult with a healthcare provider. They can help interpret your BMI in context with other health indicators and recommend appropriate actions.