1. What is BMI?

Body Mass Index (BMI) is a simple calculation using a person's height and weight. The formula is BMI = kg/m² where kg is a person's weight in kilograms and m² is their height in meters squared. BMI provides a reliable indicator of body fatness for most people.

2. How Does the Calculator Work?

The calculator uses the BMI formula:

Where:

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

Explanation: The equation divides weight by the square of height to normalize for different body sizes.

3. Importance of BMI Calculation

Details: BMI is a simple screening tool to identify possible weight problems in adults. It helps assess whether a person is underweight, normal weight, overweight, or obese.

4. Using the Calculator

Tips: Enter weight in kilograms and height in meters. For height in centimeters, divide 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 BMI categories?
A: Underweight (BMI < 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: Should children use this calculator?
A: No, children and teens need age- and sex-specific percentiles rather than fixed categories.

Q4: What's a healthy BMI range?
A: For most adults, 18.5 to 24.9 is considered healthy.

Q5: What if I know my height in feet/inches?
A: Convert to meters: 1 foot = 0.3048 meters, 1 inch = 0.0254 meters.