1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. BMI provides a reliable indicator of body fatness for most people.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Body weight in kilograms (kg)
• \( height \) — Height in meters (m)

Explanation: The formula divides weight by the square of height to account for the fact that weight increases with the square of height.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive screening method for weight categories that may lead to health problems. It's used to screen for weight categories that may lead to health problems but it is not diagnostic of body fatness or health.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, and age in years. All values must be valid (weight > 0, height > 0, age between 1-120).

5. Frequently Asked Questions (FAQ)

Q1: What are the BMI categories for adults?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), and Obese (≥30).

Q2: Is BMI interpreted the same way for children as adults?
A: No, BMI for children is age and sex-specific and is referred to as BMI-for-age percentile.

Q3: What are the limitations of BMI?
A: BMI doesn't directly measure body fat and doesn't account for muscle mass, bone density, or fat distribution.

Q4: How often should BMI be checked?
A: For adults, annual checks are typically sufficient unless significant weight changes occur.

Q5: Are there better alternatives to BMI?
A: More precise measures include skinfold thickness, bioelectrical impedance, DXA, and underwater weighing, but these are more complex and expensive.