1. What is BMI?

Body Mass Index (BMI) is a value derived from the mass and height of a person. The BMI is defined as the body mass divided by the square of the body height, and is expressed in units of kg/m².

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

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

Explanation: The equation calculates body mass index using imperial units (stones and inches) with appropriate conversion factors.

3. Importance of BMI Calculation

Details: BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.

4. Using the Calculator

Tips: Enter weight in stones and height in inches. All values must be valid (weight > 0, height > 0). For most adults, an ideal BMI is in the 18.5 to 24.9 range.

5. Frequently Asked Questions (FAQ)

Q1: What is a healthy BMI range?
A: For most adults, 18.5 to 24.9 is healthy, 25 to 29.9 is overweight, and 30 or above is obese.

Q2: Are there limitations to BMI?
A: BMI doesn't distinguish between muscle and fat, so athletes may have high BMI without excess fat. It also may not be accurate for children, elderly, or pregnant women.

Q3: How do I convert stones to pounds?
A: 1 stone equals 14 pounds. The calculator automatically handles this conversion.

Q4: Why use stones instead of pounds or kg?
A: This calculator follows the NHS standard which commonly uses stones for weight measurement in the UK.

Q5: Should BMI be the only measure of healthy weight?
A: No, waist circumference and other factors should also be considered for a complete assessment.