1. What is BMI?

BMI (Body Mass Index) is a measure of body fat based on height and weight that applies to adult men and women. It provides a simple numeric measure of a person's thickness or thinness.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

• \( weight \) — Body weight in kilograms (kg)
• \( height \) — Height in inches (in)
• 39.37 — Conversion factor from inches to meters

Explanation: The formula converts height from inches to meters, then calculates weight divided by height squared.

3. Importance of BMI Calculation

Details: BMI is used to screen for weight categories that may lead to health problems. It's a simple, inexpensive method to assess weight status.

4. Using the Calculator

Tips: Enter weight in kilograms and height in inches. All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: What are the BMI categories?
A: Underweight (<18.5), Normal (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 kg and inches?
A: This calculator specifically uses kilograms for weight and inches for height as requested.

Q4: How often should I check my BMI?
A: For most adults, checking every few months is sufficient unless undergoing significant weight changes.

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