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BMI Calculator

Calculate your Body Mass Index (BMI) using Australian health guidelines. Includes healthy weight ranges, health risk assessment, and BMI-for-age reference for children.

Your Measurements
Units
Height ?
cm
Weight ?
kg
Age ?
years
Sex
Your BMI Result
Your BMI
24.5
Normal Weight
Underweight
<18.5
Normal
18.5–25
Overweight
25–30
Obese
>30
CategoryBMI RangeYour Status

Healthy Weight Range for Your Height

BMI in Australia — ABS & AIHW Guidelines

According to the Australian Institute of Health and Welfare (AIHW), approximately two-thirds of Australian adults are overweight or obese (BMI ≥ 25). BMI is used as a population-level screening tool, not a diagnostic measure.

Australian BMI Categories (WHO / ABS)

CategoryBMI RangeHealth Risk
UnderweightBelow 18.5Increased risk (nutritional deficiency)
Normal weight18.5 – 24.9Lowest risk
Overweight25.0 – 29.9Increased risk
Obese Class I30.0 – 34.9High risk
Obese Class II35.0 – 39.9Very high risk
Obese Class III40.0 and aboveExtremely high risk

BMI Limitations

BMI does not account for muscle mass, bone density, body fat distribution, age, or ethnicity. Athletes may have a high BMI despite low body fat. The AIHW recommends using BMI alongside waist circumference measurements for a more complete picture.

Waist Circumference (Australian Guidelines)

Waist circumference is a useful indicator of abdominal fat. Australian health guidelines recommend: men below 94 cm (risk) and below 102 cm (high risk); women below 80 cm (risk) and below 88 cm (high risk).

Children and Adolescents

For children aged 2–18, BMI must be interpreted using age- and sex-specific BMI-for-age percentiles (from the Australian growth reference charts). Adult BMI cut-offs do not apply to children.

Medicare and Weight Management

Australians with a BMI over 30 who have a related chronic condition may be eligible for a GP Management Plan (GPMP) under Medicare, providing access to subsidised allied health services including dietitians and exercise physiologists.