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 to Calculate BMI

The BMI formula is:

Example Calculation: For a person who weighs 70kg and is 1.75m tall:

• BMI = 70 ÷ (1.75 × 1.75)
• BMI = 70 ÷ 3.0625
• BMI = 22.9 kg/m²

3. BMI Categories

Standard BMI Categories:

• Underweight: BMI less than 18.5
• Normal weight: BMI 18.5 to 24.9
• Overweight: BMI 25 to 29.9
• Obese: BMI 30 or greater

Note: BMI categories may vary slightly for different populations (e.g., Asian populations may have different cutoff points).

4. Using the Calculator

Instructions: Enter your weight in kilograms and height in meters. For height, you can convert from cm to m by dividing by 100 (e.g., 175cm = 1.75m).

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for everyone?
A: BMI may not accurately reflect body fat in athletes (who have more muscle mass) or elderly (who may have lost muscle mass).

Q2: What's the difference between BMI for adults and children?
A: For children, BMI is age and sex-specific and is referred to as BMI-for-age.

Q3: Should I use pounds and inches?
A: The formula changes to (weight in pounds ÷ height in inches²) × 703 when using imperial units.

Q4: What are the limitations of BMI?
A: BMI doesn't distinguish between muscle and fat, and doesn't account for fat distribution which affects health risks.

Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, but individual circumstances may vary.