Body mass index or BMI is used to determine whether you are in a healthy weight range for your height. Learn more about your body mass index.
WHAT IS BODY MASS INDEX (BMI)?
The body mass index (BMI) is a great way to establish whether or not you’re in a healthy weight range and is based on height and weight. The BMI is a useful measurement for most people over 18 years, however, there are some limitations to be aware of as it may be influenced by age, gender and ethnicity.
What The Results Mean
Based on your BMI calculation, you can determine your classification based on the chart below.
Classification | BMI(kg/m2) | |
Principal cut-off points | Additional cut-off points | |
Underweight | <18.50 | <18.50 |
Severe thinness | <16.00 | <16.00 |
Moderate thinness | 16.00 - 16.99 | 16.00 - 16.99 |
Mid thinness | 17.00 - 18.49 | 17.00 - 18.49 |
Normal range | 18.50 - 24.99 | 18.50 - 22.99 |
23.00 - 24.99 | ||
Overweight | ≥ 25.00 | ≥ 25.00 |
Pre-obese | 25.00 - 29.99 | 25.00 - 27.49 |
27.50 - 29.99 | ||
Obese | ≥ 30.00 | ≥ 30.00 |
Obese class I | 30.00 - 34.99 | 30.00 - 32.49 |
32.50 - 34.99 | ||
Obese class II | 35.00 - 39.99 | 35.00 - 37.49 |
37.50 - 39.99 | ||
Obese class III | ≥ 40.00 | ≥ 40.00 |
Source: Adapted from World Health Organisation (WHO) 1995, WHO 2000 and WHO 2004.
EXCEPTIONS TO THE RULE
Muscles: BMI cannot distinguish between fat and muscle. Those with higher than average muscle mass (body builders, athletes etc.) will end up with a misleadingly high BMI value.
Certain populations: BMI and the above mentioned classification are also unsuitable for certain populations and individuals, including Aboriginal people, Pacific Islanders, Asian people, children, pregnant women and the elderly.
For all these reasons, you should treat it as a rough guide to be used in conjunction with other body-weight indicators.
WAIST CIRCUMFERENCE
Measuring your waist circumference is a great predictor of your health. No matter what your height or build are, an increased waist line can be a sign that your health is more at risk.
The BMI calculation is a guideline only as it does not take into consideration fat to muscle ration, which affects BMI results. Therefore, it may not be appropriate for athletes or those of muscular build.
The calculations on this site are estimates and content is provided for general information only. It should not be treated as a substitute for the medical advice of your own doctor or any other health care professional. Always consult your own GP if you’re in any way concerned about your health.