1. What is BMI?

Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, normal weight, overweight and obesity in adults. It provides a useful population-level measure of weight status.

2. How is BMI Calculated?

The calculator uses the standard BMI formula:

Where:

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

Explanation: BMI correlates fairly well with body fat in most people, though it doesn't directly measure body fat.

3. BMI Categories

Standard Categories:

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

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For pounds and inches, convert first (1 kg = 2.2 lbs, 1 m = 39.37 inches).

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: What is a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, though individual health depends on other factors too.

Q3: How often should I check my BMI?
A: Periodic checks (every few months) can help track weight changes, but daily fluctuations are normal.

Q4: Does BMI apply to children?
A: Children's BMI is interpreted differently using age- and sex-specific percentile charts.

Q5: What's better than BMI?
A: Waist circumference, body fat percentage, and other measurements may provide more complete health assessment.