🏃 Health & Fitness Calculators

Free Australian health calculators covering fitness, nutrition, pregnancy, and clinical health. Based on NHMRC, RANZCOG, ABS, and Heart Foundation Australia guidelines.

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💪 Fitness Calculators

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Army Body Fat Calculator NEW

Military tape method (ADF/US Army). Calculate body fat % from neck, waist, and hip measurements.

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Lean Body Mass Calculator

Calculate fat-free mass using Boer, James, Hume, and Peters formulas. Used for drug dosing and sports nutrition.

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Healthy Weight Calculator Popular

Find your healthy weight range by height using Australian BMI guidelines (18.5–24.9) and multiple IBW formulas.

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Calories Burned Calculator Popular

60+ activities including AFL, netball, swimming, running. Results in kcal and kJ. Based on MET values.

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One Rep Max (1RM) Calculator

Estimate 1RM from any weight and reps using 8 formulas. Includes full training percentage table.

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Target Heart Rate Calculator

Calculate all 5 heart rate training zones using Karvonen and %MHR methods. Heart Foundation Australia reference.

📊 Body Composition & Vitals

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BMI Calculator Most popular

Body Mass Index calculator with ABS and AIHW Australian population reference data. Adults and children.

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Body Fat Calculator

US Navy method and BMI-based formula. With DEXA scan reference and waist circumference guidelines.

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BMR Calculator

Basal Metabolic Rate using Mifflin-St Jeor, Harris-Benedict, and Katch-McArdle. Outputs kJ and kcal.

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Ideal Weight Calculator

Devine, Robinson, Miller, and Hamwi formulas. Australian AIHW healthy weight range comparison.

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Body Type Calculator NEW

Discover your somatotype (ectomorph, mesomorph, or endomorph) and get tailored training and nutrition advice.

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Body Surface Area Calculator NEW

BSA using Mosteller, DuBois, Haycock, and Boyd formulas. Used for drug dosing in Australian hospitals.

🥗 Nutrition & Diet Calculators

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Calorie Calculator Popular

Daily calorie needs using NHMRC dietary guidelines. kJ and kcal output. Australian food label reference.

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TDEE Calculator NEW

Total Daily Energy Expenditure using Mifflin-St Jeor, Harris-Benedict. Compare all activity levels. kJ output.

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Macro Calculator NEW

Protein, carb, and fat targets based on NHMRC AMDRs. Supports balanced, low-carb, high-protein, and keto ratios.

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Protein Calculator NEW

Daily protein requirements from 0.75g/kg (NHMRC RDI) to 2.2g/kg (elite athletes). Sports Dietitians Australia reference.

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Carbohydrate Calculator NEW

Daily carb targets for general health to endurance athletes. NHMRC AMDR 45–65% of energy.

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Fat Intake Calculator NEW

Total fat, saturated fat, omega-3 targets per NHMRC. Supports standard, Mediterranean, low-fat, and keto diets.

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Pace Calculator

Running pace, speed, distance, and time. parkrun, City2Surf, and Melbourne/Sydney Marathon reference times.

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BAC Calculator NEW

Blood alcohol concentration estimator. Australian drink-driving limits (0.05 general, 0.00 P-plates). DrinkWise reference.

🏥 Clinical Health Calculators

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GFR / Kidney Function Calculator NEW

eGFR using CKD-EPI equation with full CKD staging (G1–G5) per Kidney Health Australia KDIGO guidelines.

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Healthy Weight Calculator

Find ideal weight range for your height based on Australian BMI guidelines (18.5–24.9). Multiple IBW formulas.

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Lean Body Mass Calculator

Used for clinical drug dosing calculations. Boer, James, Hume, Peters formulas.

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Body Surface Area (BSA)

Mosteller formula (preferred in Australian hospitals) plus DuBois, Haycock, Boyd, and Gehan formulas.

🤰 Pregnancy & Women's Health Calculators

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Pregnancy Calculator Popular

Due date, current week, trimester, week-by-week development, and full RANZCOG antenatal care schedule.

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Due Date Calculator NEW

Calculate EDD from LMP, conception, ultrasound, or IVF transfer. Full trimester dates and term window.

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Pregnancy Weight Gain Calculator NEW

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Pregnancy Conception Calculator NEW

Find your conception date from LMP or due date. Includes fertile window and ovulation timing.

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Ovulation Calculator NEW

Fertile window and ovulation date prediction. Colour-coded fertility calendar for up to 6 cycles.

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Conception Calculator NEW

Reverse-calculate conception date from EDD or LMP. Bidirectional — find EDD from conception date.

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Period Calculator NEW

Predict upcoming period dates for up to 12 months. Jean Hailes Foundation Australia reference.

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Baby Due Date (LMP method)

Classic Naegele's Rule calculator with LMP input. Weekly development guide included.

🩺 More Health Calculators

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Target Heart Rate

5 training zones with Karvonen and %MHR methods. RHR fitness assessment. Heart Foundation Australia.

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BMI Calculator

Australian BMI with ABS reference values. Adults and children. Waist circumference risk guide.

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Pregnancy Week Calculator

How many weeks pregnant are you? RANZCOG antenatal schedule. Medicare bulk-billed visits.

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Running Pace Calculator

Pace / speed / time / distance. City2Surf, parkrun, Melbourne Marathon reference times.

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BMR Calculator

Basal Metabolic Rate using 4 formulas. NHMRC kJ output. Foundation for all calorie calculations.

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Sleep Calculator

Optimal bed and wake times based on 90-min sleep cycles. Sleep Health Foundation Australia guidelines.

⚕️ Medical Disclaimer: All calculators on MegaCalcOnline.com are for informational and educational purposes only. They do not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional — GP, dietitian, midwife, or specialist — before making health decisions.