Body Mass Index Calculator

BMI Formula:

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

Body Mass Index (BMI):

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1. What is Body Mass Index?

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.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

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

Where:

\( weight \) — Body weight in kilograms
\( height \) — Height in meters

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

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.

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: Should children use the same BMI categories?
A: No, children's BMI is interpreted relative to growth charts for their age and sex.

Q4: What are the health risks associated with high BMI?
A: Higher BMI is associated with increased risk of heart disease, diabetes, and certain cancers.

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