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 BMI formula:

Where:

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

Explanation: The equation divides weight by the square of height to account for the relationship between height and body surface area.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive screening tool 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's not diagnostic of body fatness or health.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. All values must be valid (weight > 0, height > 0). For height in centimeters, divide by 100 to convert to meters.

5. Frequently Asked Questions (FAQ)

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

Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and others with muscular builds, and underestimate body fat in older persons and others who have lost muscle.

Q3: What are the limitations of BMI?
A: BMI doesn't directly measure body fat and doesn't account for factors like muscle mass, bone density, overall body composition, and racial/sex differences.

Q4: Should children use the same BMI categories?
A: No, children and teens need BMI-for-age percentiles that consider sex and age due to varying body composition as they grow.

Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, but individual health risks should be assessed by a healthcare professional.