1. What is BMI?

Body Mass Index (BMI) is a value derived from the mass and height of a person. It provides a simple numeric measure of a person's thickness or thinness, allowing health professionals to discuss weight problems more objectively with their patients.

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 categorize their weight status.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive screening method for weight category—underweight, healthy weight, overweight, and obesity. It correlates fairly well with body fat in most people.

4. Using the Calculator

Tips: Enter weight in kilograms, height in meters, and age in years. All values must be valid (weight > 0, height > 0, age between 1-120).

5. Frequently Asked Questions (FAQ)

Q1: What are the 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 athletes and underestimate it in older people who have lost muscle mass.

Q3: Why include age in the calculator?
A: While age doesn't affect the BMI calculation, it helps provide age-appropriate interpretation of results.

Q4: What's a healthy BMI for my age?
A: The standard categories apply to adults of all ages, though older adults may have slightly higher optimal ranges.

Q5: Should children use this calculator?
A: Children need BMI-for-age percentiles rather than standard BMI categories.