Body Mass Index Calculator

BMI Formula:

\[ BMI = \frac{W}{H^2} \]

BMI (kg/m²):

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1. What is Body Mass Index (BMI)?

Definition: BMI is a numerical value derived from an individual's weight and height that provides a reliable indicator of body fatness for most people.

Purpose: It is used to screen for weight categories that may lead to health problems but is not diagnostic of body fatness or health.

2. How Does the BMI Calculator Work?

The calculator uses the formula:

\[ BMI = \frac{W}{H^2} \]

Where:

\( BMI \) — Body Mass Index (kg/m²)
\( W \) — Weight (kilograms)
\( H \) — Height (meters)

Explanation: The weight in kilograms is divided by the square of height in meters to calculate BMI.

3. BMI Categories

Details:

Underweight: BMI < 18.5
Normal weight: BMI 18.5-24.9
Overweight: BMI 25-29.9
Obesity: BMI ≥ 30

4. Using the Calculator

Tips: Enter your weight in kilograms and height in meters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and underestimate it in older people who have lost muscle mass.

Q2: How do I convert pounds to kilograms?
A: Multiply pounds by 0.453592 to get kilograms.

Q3: How do I convert feet/inches to meters?
A: Multiply feet by 0.3048 and inches by 0.0254, then add them together.

Q4: Why is BMI important?
A: BMI is a simple screening tool that can indicate whether someone is at a healthy weight for their height.

Q5: Should children use this calculator?
A: Children's BMI is interpreted differently than adults and should be assessed using age- and sex-specific percentiles.