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BMI Calculator

BMI Formula:

\[ BMI = \frac{Weight}{Height^2} \]

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meters

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1. What is BMI?

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 defined as a person's weight in kilograms divided by the square of their height in meters (kg/m²).

2. How Does the Calculator Work?

The calculator uses the BMI formula:

\[ BMI = \frac{Weight\ (kg)}{Height^2\ (m^2)} \]

Where:

Explanation: The formula calculates body mass per unit of surface area, providing a standardized way to compare weights across different heights.

3. Importance of BMI Calculation

Details: BMI provides a simple numeric measure that helps healthcare professionals identify potential weight problems in adults. While not a direct measure of body fat, it correlates well with more direct measures of body fat.

4. Using the Calculator

Tips: Enter your 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).

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: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI percentiles rather than the adult categories.

Q4: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy.

Q5: Are there better measures than BMI?
A: Waist circumference and body fat percentage measurements may provide additional useful information.

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