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Health & Fitness Calculators

Calculate your BMI, daily calorie needs and pregnancy due date with our free health tools.

3 calculatorsFree · No signup · ATO data

About Health Calculators

Body Mass Index (BMI) is calculated as weight (kg) divided by height (m) squared. A healthy BMI range is 18.5 to 24.9. Our calculator supports both metric (cm/kg) and imperial (inches/lbs) units. BMI is a useful screening tool but does not account for muscle mass or body composition.

Daily calorie needs vary by age, gender, weight, and activity level. The Mifflin-St Jeor equation provides the most accurate estimate of Basal Metabolic Rate (BMR). A 500-calorie daily deficit typically results in approximately 0.5kg of weight loss per week — a safe and sustainable rate.

Pregnancy due dates are calculated as 280 days (40 weeks) from the first day of the last menstrual period — the standard Naegele's rule. Only about 5% of babies arrive on their exact due date. The 20-week anatomy scan is a key milestone during the second trimester.

Official sources: Health Direct BMI

Built by Konstantin Iakovlev. Data sourced from official Australian government publications.