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 and is used to screen for weight categories.

2. How to Calculate BMI

The BMI calculation formula is:

Where:

• Weight — Measured in kilograms (kg)
• Height — Measured in meters (m)

Example: For a person who weighs 70kg and is 1.75m tall:
BMI = 70 ÷ (1.75 × 1.75) = 22.9 kg/m²

3. BMI Categories in Australia

Australian Standard Categories:

• Underweight: BMI less than 18.5
• Healthy weight: BMI 18.5 to 24.9
• Overweight: BMI 25.0 to 29.9
• Obese: BMI 30 or greater

4. Using the Calculator

Instructions: Enter your weight in kilograms and height in meters. For height, you can convert from cm to m by dividing by 100 (e.g., 175cm = 1.75m).

5. Frequently Asked Questions (FAQ)

Q1: Is BMI accurate for everyone?
A: BMI is a useful screening tool but doesn't directly measure body fat. It may not be accurate for athletes with high muscle mass, pregnant women, or the elderly.

Q2: What's a healthy BMI range in Australia?
A: For Australian adults, a BMI between 18.5 and 24.9 is considered healthy.

Q3: Should children use this calculator?
A: No, children and teens need age- and sex-specific BMI calculations. Consult a pediatrician for accurate assessment.

Q4: How often should I check my BMI?
A: For most adults, checking every 6-12 months is sufficient unless you're actively trying to change your weight.

Q5: Where can I get more health advice in Australia?
A: Visit the Australian Government Department of Health website or consult your GP for personalized advice.