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BMI Calculator

BMI Formula:

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

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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 the weight in kilograms divided by the square of the height in meters.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

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

Where:

Explanation: The formula calculates body mass per unit of height squared, providing a standardized measure of body composition.

3. Importance of BMI Calculation

Details: BMI is a quick screening tool for potential weight problems in adults. While it doesn't measure body fat directly, research has shown that BMI correlates to direct measures of body fat.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For height, you can convert from centimeters 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 persons who have lost muscle mass.

Q3: How often should I check my BMI?
A: Periodic checks (every 6-12 months) can help track changes, but more frequent measurements aren't typically needed.

Q4: Can children use this calculator?
A: Children and teens need age- and sex-specific percentiles rather than the adult categories.

Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, though individual factors should be considered.

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