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Body Mass Index Calculator

BMI Formula:

\[ BMI = \frac{weight\ (kg)}{height^2\ (m)} \]

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meters

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1. What is Body Mass Index (BMI)?

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 the weight in kilograms divided by the square of the height in meters (kg/m²).

2. How Does the Calculator Work?

The calculator uses the BMI formula:

\[ BMI = \frac{weight\ (kg)}{height^2\ (m)} \]

Where:

Explanation: The formula calculates body mass per unit of surface area, providing a standardized way to assess weight status.

3. Importance of BMI Calculation

Details: BMI provides a useful population-level measure of overweight and obesity. It is a simple, non-invasive way to screen for weight categories that may lead to health problems.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For pounds and inches, first convert to metric units (1 kg = 2.2 lbs, 1 m = 39.37 inches).

5. Frequently Asked Questions (FAQ)

Q1: What are the standard BMI categories?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), Obese (≥30).

Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and underestimate it in older people who have lost muscle mass.

Q3: What is a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy.

Q4: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI percentiles.

Q5: What's better than BMI for measuring health?
A: Waist circumference, body fat percentage, and other measurements combined with BMI give a better health picture.

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