BMI Calculator
Calculate your Body Mass Index and see which weight category you fall into.
How It Works
BMI is calculated as weight (kg) divided by height (m) squared: BMI = weight / height². The calculator then classifies your result into standard WHO categories and shows the healthy weight range for your height (BMI 18.5-24.9). It also estimates the weight you'd need to reach to move to a lower category.
Frequently Asked Questions
What are the BMI categories?
WHO categories: Underweight < 18.5, Normal weight 18.5-24.9, Overweight 25.0-29.9, Obese class I 30.0-34.9, Obese class II 35.0-39.9, Obese class III 40.0+. For people of Asian background, overweight begins at 23.0 and obese at 27.5.
Is BMI accurate for everyone?
BMI has limitations. It doesn't distinguish between muscle and fat, so athletes may be classified as overweight. It may also underestimate body fat in older adults who have lost muscle mass. Waist circumference is a useful additional measure.
What is a healthy weight for an Australian adult?
According to the Australian Institute of Health and Welfare, a healthy BMI is 18.5-24.9. In 2022, about 67% of Australian adults were overweight or obese. Maintaining a healthy weight reduces risk of type 2 diabetes, heart disease, and certain cancers.
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