1. What is BMI?

Definition: Body Mass Index (BMI) is a value derived from the mass (weight) and height of a person.

Purpose: BMI is a simple index of weight-for-height that is commonly used to classify underweight, normal weight, overweight and obesity in adults.

2. How Does the BMI Calculator Work?

The calculator uses the formula:

Where:

• \( BMI \) — Body Mass Index (kg/m²)
• \( W \) — Weight (kilograms)
• \( H \) — Height (meters)

Explanation: The weight in kilograms is divided by the square of the height in meters.

3. BMI Categories

Standard Categories:

• Underweight: BMI < 18.5
• Normal weight: BMI 18.5–24.9
• Overweight: BMI 25–29.9
• Obesity: BMI ≥ 30

4. Using the Calculator

Tips: Enter your weight in kilograms and height in meters. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: Why is BMI important?
A: BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems objectively.

Q2: Is BMI accurate for everyone?
A: BMI may not be accurate for athletes (who may have high muscle mass), pregnant women, or the elderly. It's a general screening tool.

Q3: How often should I check my BMI?
A: For most adults, checking BMI annually is sufficient unless you're actively trying to change your weight.

Q4: What's a healthy BMI range?
A: For most adults, a BMI between 18.5 and 24.9 is considered healthy.

Q5: Where can I learn more about BMI?
A: Consult with your healthcare provider or visit reputable health websites like CDC or WHO.