BMI Calculator — Check Your Body Mass Index
Calculate your Body Mass Index (BMI) quickly and easily. Enter your height and weight to see where you sit on the healthy weight scale, your ideal target weight range, and what your result means for your health — plus how a telehealth GP can help you act on it.
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BMI Calculator
Enter your details below. Your result appears instantly — nothing is stored or sent anywhere.
What Is BMI?
Body Mass Index (BMI) is a widely used screening measure that estimates whether your weight is in a healthy range for your height. It is calculated by dividing your weight in kilograms by the square of your height in metres (kg/m²). Health organisations including the WHO and Australia's Department of Health use BMI as a population-level indicator of healthy weight.
Why BMI Matters
A BMI outside the healthy range can be associated with higher risks of conditions like type 2 diabetes, heart disease, high blood pressure and sleep apnoea. It's a useful early signal that a conversation with a doctor may be worthwhile.
BMI's Limitations
BMI doesn't distinguish muscle from fat, so very muscular people can appear "overweight", and it may not suit older adults, pregnant women or certain ethnic groups. Treat it as a starting point, not a diagnosis.
What the BMI Categories Mean
The World Health Organization's adult BMI classification ranges.
Underweight
Being underweight can carry its own health risks, including nutrient deficiencies and weakened immunity. A GP can help identify causes and a healthy plan to gain weight safely.
Healthy Weight
This range is associated with the lowest health risk for most adults. Regular check-ups and healthy habits help you maintain it.
Overweight
A BMI in this range may increase the risk of weight-related health conditions. Small, sustainable changes and GP-guided support can make a big difference.
Obese
A BMI of 30+ is associated with a significantly higher risk of chronic conditions. A structured, medically supervised weight management plan is recommended.
What to Do with Your Result
Whether your BMI is high, low or healthy — here's how a telehealth GP can help.
Calculate Your BMI
Use the calculator above and note your result and ideal target weight range. You can copy it for your consultation.
Book a GP Consultation ($49)
Discuss your BMI and overall health with an AHPRA-registered GP by phone or video. Your doctor considers the full picture — diet, activity, medications and history.
Get a Personalised Plan
Receive tailored guidance, pathology or specialist referrals if clinically appropriate, and a plan you can actually stick to.
Weight Management Support
Get personalised nutrition strategies, medical guidance and a custom weight management plan built for you by an experienced telehealth GP.
Book Weight Management Consultation ($49)Frequently Asked Questions
Common questions about BMI and healthy weight.
BMI is your weight in kilograms divided by your height in metres squared (kg/m²). In imperial units, the calculator converts your height and weight to metric before applying the same formula. The calculator above does this for you instantly.
For most adults, a healthy BMI is between 18.5 and 24.9. Below 18.5 is considered underweight, 25.0–29.9 is overweight, and 30.0 or above is classified as obese. These ranges apply to adults aged 18 and over.
Not always. BMI doesn't distinguish muscle from fat, so athletes can register as "overweight" despite low body fat. It may also be less meaningful for adults over 65, pregnant women and children. Use it as one indicator alongside professional advice.
No. All calculations happen locally in your browser — your height, weight and results are never sent to or stored on our servers.
Book a GP consultation. A doctor can assess your overall health, rule out underlying causes, and help you build a safe, sustainable plan — whether your goal is weight loss, weight gain or maintaining good health.
A full GP telehealth consultation is $49. See our pricing & fees page for the full list of services and prices.
Want a Personalised Weight Plan?
Book a telehealth consultation with an AHPRA-registered GP and get medical guidance built around your body, your lifestyle and your goals.