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 standard BMI formula:

Where:

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

Explanation: The formula divides your weight by the square of your height to give a number that helps categorize your weight status.

3. Importance of BMI Calculation

Details: BMI is a simple, inexpensive screening method for weight category—underweight, healthy weight, overweight, and obese. It's used to identify potential weight problems in adults.

4. Using the Calculator

Tips: Enter your weight in kilograms and height in meters. For New Zealand men, the same BMI categories apply as for the general adult population.

5. Frequently Asked Questions (FAQ)

Q1: What are the BMI categories for adults?
A: Underweight (<18.5), Normal weight (18.5-24.9), Overweight (25-29.9), Obese (≥30).

Q2: Is BMI different for men and women?
A: The same BMI ranges apply to both men and women, though men tend to have more muscle mass which can affect interpretation.

Q3: What are the BMI ranges used in New Zealand?
A: New Zealand uses the standard WHO BMI categories, though Pacific and Māori populations may have different health risks at the same BMI.

Q4: What are the limitations of BMI?
A: BMI doesn't distinguish between muscle and fat, so very muscular people may have a high BMI without excess fat. It also doesn't account for fat distribution.

Q5: Should athletes use BMI?
A: Athletes with high muscle mass may want to use additional measures like body fat percentage, as BMI may overestimate their body fat.