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 (kg/m²).

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 an inexpensive and easy screening method for weight category—underweight, healthy weight, overweight, and obesity. It correlates moderately well with direct measures of body fatness.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. 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), Obesity (≥30)

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

Q3: Is BMI accurate for athletes?
A: BMI may overestimate body fat in athletes and others with muscular builds.

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

Q5: What are healthy BMI ranges for older adults?
A: Some research suggests a BMI range of 23-27 may be optimal for older adults.