1. What is BMI?

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

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Weight in pounds (lbs)
• \( feet \) — Height in feet component
• \( inches \) — Height in inches component
• 703 — Conversion factor (kg/m² to lbs/in²)

Explanation: The equation converts height to total inches, then calculates the ratio of weight to height squared with appropriate unit conversion.

3. Importance of BMI Calculation

Details: BMI is a simple screening tool for weight categories that may lead to health problems. It helps identify potential weight problems in adults, though it doesn't diagnose body fatness or health directly.

4. Using the Calculator

Tips: Enter weight in pounds, and height in feet and inches. All values must be valid (weight > 0, height > 0). For most accurate results, measure weight without heavy clothing and height without shoes.

5. Frequently Asked Questions (FAQ)

Q1: What are the BMI categories?
A: Underweight (<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 people with lost muscle mass.

Q3: Why use pounds and feet instead of metric?
A: This calculator is designed for the US customary units system commonly used in the United States.

Q4: How often should I check my BMI?
A: For most adults, checking every few months is sufficient unless you're actively trying to change your weight.

Q5: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI percentiles rather than adult categories.