1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. BMI provides a reliable indicator of body fatness for most people.

2. How Does the Calculator Work?

The calculator uses the standard BMI formula:

Where:

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

Explanation: The formula divides your weight in kilograms by the square of your height in meters to categorize your weight status.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive screening tool for weight categories that may lead to health problems. It's used to screen for weight categories that may lead to health problems but it's not diagnostic of body fatness or health.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For pounds and inches, convert first (1 kg = 2.2 lbs, 1 m = 39.37 inches). 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), Obese (≥30).

Q2: 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.

Q3: Should children use the same BMI categories?
A: No, children and teens need age- and sex-specific percentiles because their body composition varies as they grow.

Q4: What are the limitations of BMI?
A: BMI doesn't measure body fat directly, and doesn't account for muscle mass, bone density, overall body composition, or racial/sex differences.

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