1. What is BMI?

Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, normal weight, overweight and obesity in adults. It's calculated using pounds and inches in this formula.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

• \( weight \) — Body weight in pounds (lbs)
• \( height \) — Height in inches
• \( 703 \) — Conversion factor to adjust units

Explanation: The formula calculates body mass per unit of height squared, providing a standardized measure of body composition.

3. Importance of BMI Calculation

Details: BMI is widely used as a screening tool to identify possible weight problems in adults. While it doesn't measure body fat directly, research has shown that BMI correlates to direct measures of body fat.

4. Using the Calculator

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

5. Frequently Asked Questions (FAQ)

Q1: What are the BMI categories for adults?
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 people who have lost muscle mass.

Q3: Why is 703 used in the formula?
A: This is the conversion factor needed when using pounds and inches (kg/m² × 703 = lbs/in²).

Q4: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI percentiles rather than adult categories.

Q5: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, though individual health factors should also be considered.