1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight. It provides a reliable indicator of body fatness for most people and is used to screen for weight categories.

2. How Does the Calculator Work?

The calculator uses the BMI equation for pounds and inches:

Where:

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

Explanation: The formula compares your weight to your height to determine if you're underweight, normal weight, overweight, or obese.

3. Importance of BMI Calculation

Details: BMI is a quick screening tool for potential weight problems in adults. While it doesn't measure body fat directly, research has shown it correlates with 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?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), Obesity (≥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: Should children use this calculator?
A: No, children and teens need age- and sex-specific percentiles rather than the adult categories.

Q4: What's the difference between this and metric BMI?
A: This version uses pounds and inches instead of kilograms and meters, but gives the same final BMI value.

Q5: 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.