1. What is BMI?

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

Purpose: The BMI is a simple, inexpensive screening method for weight category—underweight, healthy weight, overweight, and obesity.

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 height in meters.

3. BMI Categories

Details:

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

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: Is BMI accurate for everyone?
A: BMI may not be accurate for athletes (high muscle mass), pregnant women, or the elderly.

Q2: How do I convert pounds to kilograms?
A: 1 pound = 0.453592 kilograms. Multiply pounds by 0.453592 to get kilograms.

Q3: How do I convert feet/inches to meters?
A: 1 foot = 0.3048 meters, 1 inch = 0.0254 meters. For example, 5'7" = (5×0.3048) + (7×0.0254) = 1.7018 meters.

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

Q5: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI calculations.