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Weight Body Mass Index Calculator

BMI Formula:

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

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1. What is Body Mass Index (BMI)?

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).

2. How Does the Calculator Work?

The calculator uses the BMI formula:

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

Where:

Explanation: The formula calculates body mass index by dividing weight by the square of height, providing a standardized measurement of body fatness.

3. Importance of BMI Calculation

Details: 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. It is used 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 accurate results, measure weight without heavy clothing and height without shoes. All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: What are the standard 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 accurately reflect body fatness in athletes (who may have high muscle mass), the elderly (who may have lost muscle mass), or certain ethnic groups.

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: Can children use this calculator?
A: This calculator is designed for adults. Children and teens require age and sex-specific percentiles for accurate assessment.

Q5: 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.

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