1. What is BMI?

Body Mass Index (BMI) is a person's weight in kilograms divided by the square of height in meters. BMI is an inexpensive and easy screening method for weight category—underweight, healthy weight, overweight, and obesity.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

• \( weight \) — Body weight in kilograms
• \( height \) — Height in meters

Interpretation:

• Below 18.5 — Underweight
• 18.5-24.9 — Normal weight
• 25.0-29.9 — Overweight
• 30.0 and above — Obese

3. Importance of BMI Calculation

Details: BMI is a useful screening tool to identify possible weight problems in adults. However, it is not a diagnostic tool and should be used in conjunction with other assessments.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For height in centimeters, divide by 100 (e.g., 175 cm = 1.75 m). All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for everyone?
A: BMI may overestimate body fat in athletes and those with muscular builds, and underestimate it in older persons who have lost muscle mass.

Q2: What are the limitations of BMI?
A: BMI doesn't directly measure body fat and doesn't account for factors like muscle mass, bone density, or fat distribution.

Q3: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI calculations because their body composition varies as they grow.

Q4: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy, though optimal range may vary by ethnicity and other factors.

Q5: Where can I learn more about BMI?
A: The National Institutes of Health (NIH) provides extensive resources on BMI and its interpretation at www.nhlbi.nih.gov.