1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight to assess body fatness. It provides a reliable indicator of body fat for most people and is used to screen for weight categories that may lead to health problems.

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 divides a person's weight by the square of their height to produce a value that correlates with body fat percentage.

3. Importance of BMI Calculation

Details: BMI is a quick screening tool for weight categories that may lead to health problems. It helps identify potential weight problems in adults, though it's not a diagnostic tool.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters. Age is optional but provides context (BMI interpretation varies slightly by age). 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: Does BMI work for everyone?
A: BMI may overestimate body fat in athletes and underestimate it in older people who have lost muscle mass.

Q3: How does age affect BMI interpretation?
A: Older adults may have slightly higher optimal BMI ranges compared to younger adults.

Q4: Should children use this calculator?
A: No, children need age- and sex-specific BMI percentiles rather than adult categories.

Q5: What's next if my BMI is high?
A: Consult a healthcare provider for further assessment including waist circumference and other risk factors.