1. What is BMI?

Body Mass Index (BMI) is a simple index of weight-for-height that is commonly used to classify underweight, overweight and obesity in adults. It is defined as the weight in kilograms divided by the square of the height in meters.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

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

Explanation: BMI provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive, and non-invasive surrogate measure of body fat. While it doesn't measure body fat directly, research has shown that BMI correlates to direct measures of body fat.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. All values must be valid (weight > 0, height > 0). For pounds and inches, convert to metric units first.

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), Obesity (≥30).

Q2: Are there limitations to BMI?
A: BMI doesn't account for muscle mass, bone density, overall body composition, or racial and sex differences.

Q3: Is BMI accurate for athletes?
A: BMI may overestimate body fat in athletes and others with muscular builds, as muscle weighs more than fat.

Q4: Is BMI different for children?
A: Yes, BMI for children and teens is age- and sex-specific and is referred to as BMI-for-age.

Q5: What's a healthy BMI range for adults?
A: For most adults, an ideal BMI is in the 18.5 to 24.9 range.