1. What is BMI?

Body Mass Index (BMI) is a value derived from the mass and height of a person. It provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

• \( weight \) — Weight in pounds (converted from stones and pounds)
• \( height \) — Height in inches (converted from feet and inches)
• 703 — Conversion factor (kg/m² to lb/in²)

Explanation: The equation calculates body mass per unit of height squared to estimate body fatness.

3. Importance of BMI Calculation

Details: BMI is a simple screening tool for weight categories that may lead to health problems. It's used to identify underweight, normal weight, overweight, and obesity in adults.

4. Using the Calculator

Tips: Enter your weight in stones and pounds, and height in feet and inches. All values must be valid (weight > 0, height > 0).

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), Obese (≥30).

Q2: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and underestimate it in older persons who have lost muscle mass.

Q3: What's the difference between stones and pounds?
A: 1 stone equals 14 pounds. This is a traditional British weight measurement system.

Q4: Why use feet and inches?
A: This calculator uses the imperial system commonly used in the UK for height and weight measurements.

Q5: Should BMI be the only measure of health?
A: No, BMI should be considered along with other measurements like waist circumference and body composition.