1. What is BMI?

BMI (Body Mass Index) is a simple index of weight-for-height that is commonly used to classify underweight, normal weight, overweight and obesity in adults. It is calculated by dividing weight in kilograms by height in meters squared.

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 calculates body mass per unit of height squared, providing a standardized measure of body composition.

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 more direct measures of body fat.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For height, you can convert from cm to m by dividing by 100 (e.g., 175 cm = 1.75 m). All values must be valid (weight > 0, height > 0).

5. Frequently Asked Questions (FAQ)

Q1: What are the standard BMI categories?
A: Underweight (<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 muscular individuals and underestimate it in older people with less muscle mass.

Q3: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI percentiles rather than these adult categories.

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.

Q5: What are alternatives to BMI?
A: Waist circumference, waist-to-hip ratio, or body fat percentage measurements may provide additional information.