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

Explanation: The formula calculates body mass per unit of height squared, providing a standardized measurement across different heights.

3. Importance of BMI Calculation

Details: BMI is a simple, quick screening tool that can indicate whether someone might have health issues related to their weight. While not diagnostic, it can signal when further assessment might be needed.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For accuracy, measure height without shoes and weight with minimal clothing. All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: What are the standard BMI categories?
A: Underweight (BMI < 18.5), Normal weight (18.5-24.9), Overweight (25-29.9), and 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: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI percentiles rather than adult categories.

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

Q5: Why use metric units?
A: The standard BMI formula uses kg/m². For pounds/inches, the formula is [weight (lbs) / height (in)²] × 703.