Body Mass Index is used to estimate your total amount of fat. It is only an approximate measure of the best weight for your health.

This calculator is designed for men and women over the age of 18.

A healthy BMI for an adult is between 20 and 25. For older Australians over the age of 74 years, your general health may be more important than being mildly overweight. Some researchers have suggested that a BMI range of 22-26 is acceptable for older Australians.

What your BMI means


Once you have measured your BMI, you can determine your healthy weight range. If your BMI is:
  • Under 18.5 - you are very underweight and possibly malnourished.
  • 18.5 to 24.9 - you have a healthy weight range for young and middle-aged adults.
  • 25.0 to 29.9 - you are overweight
  • Over 30 - you are obese.

Some exceptions to the rule

BMI does not differentiate between body fat and muscle mass. This means there are some exceptions to the BMI guidelines.       

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Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your doctor or other registered health professional. Content has been prepared for Victorian residents and wider Australian audiences, and was accurate at the time of publication. Readers should note that, over time, currency and completeness of the information may change. All users are urged to always seek advice from a registered health care professional for diagnosis and answers to their medical questions.