All Health Tools
50 free, medically-reviewed tools and calculators, organised by category.
Heart & Cardiovascular
Heart Rate Zone Calculator
Find your maximum heart rate and the five training zones that help you exercise at the right intensity for fat burning, endurance and performance.
Target Heart Rate Calculator (Karvonen)
Calculate personalised target heart rate zones using the Karvonen method, which factors in your resting heart rate for more accurate training intensities.
Cholesterol Ratio Calculator
Calculate your total cholesterol to HDL ratio — a strong predictor of cardiovascular risk that doctors use alongside individual cholesterol numbers.
Resting Heart Rate Checker
Find out what your resting heart rate says about your cardiovascular health and fitness. Understand whether your pulse is in a healthy range.
Mean Arterial Pressure (MAP) Calculator
Calculate your mean arterial pressure — the average pressure in your arteries through one heartbeat, and a key indicator of whether your organs are getting enough blood flow.
Pulse Pressure Calculator
Calculate your pulse pressure — the difference between your systolic and diastolic blood pressure — and learn what it reveals about your arterial health.
Blood Pressure Checker
Enter your blood pressure reading to understand what it means, based on ACC/AHA categories.
Maximum Heart Rate Calculator
Estimate your maximum heart rate by age and see your moderate and vigorous exercise heart rate zones for safer, more effective training.
Diabetes & Blood Sugar
BMR Calculator
Calculate your Basal Metabolic Rate (BMR) — the number of calories your body burns at complete rest to keep you alive. The foundation for understanding your energy needs.
HbA1c to Average Glucose Converter
Convert your HbA1c percentage to estimated average blood glucose (eAG), or work backwards from your average glucose to HbA1c. Shows results in both mmol/L and mg/dL.
Blood Sugar Interpreter
Understand your blood sugar test result for fasting, random, post-meal and HbA1c.
eGFR Calculator (Kidney Function)
Estimate your kidney function (eGFR) from your creatinine level, age and sex using the CKD-EPI 2021 equation used in clinical practice worldwide.
Nutrition & Diet
Daily Calorie Calculator (TDEE)
Calculate how many calories you need each day to maintain, lose or gain weight. Uses the scientifically validated Mifflin-St Jeor equation and your activity level.
Water Intake Calculator
Find out how much water you should drink each day based on your body weight, activity level and the climate you live in. Personalised, evidence-based hydration guidance.
Macronutrient Calculator
Split your daily calories into protein, carbohydrates and fat. Set your macros for balanced eating, low-carb, high-protein or keto goals.
Protein Intake Calculator
Find out how much protein you should eat each day based on your body weight and activity level, from general health to muscle building.
Sleep Calculator
Find the best time to go to bed based on when you need to wake up, using 90-minute sleep cycles so you wake feeling refreshed rather than groggy.
Vitamin D Level Interpreter
Understand where your vitamin D blood result falls within general reference ranges.
Haemoglobin Level Interpreter
Understand where your haemoglobin result falls within general reference ranges for anaemia screening.
Weight & Obesity
BMI Calculator
Calculate your Body Mass Index (BMI) to understand whether your weight is healthy for your height. Uses World Health Organization (WHO) classification standards.
Body Fat Percentage Calculator
Estimate your body fat percentage using the U.S. Navy circumference method — a practical measure of body composition that tells you more than weight alone.
Ideal Weight Calculator
Estimate your ideal body weight using four established medical formulas. A useful reference range based on your height and sex.
Waist-to-Hip Ratio Calculator
Calculate your waist-to-hip ratio — a simple measure of fat distribution that the World Health Organization uses to assess health risk.
Body Surface Area (BSA) Calculator
Calculate your body surface area using the Mosteller formula — a measure used in medicine for drug dosing, physiology and clinical assessment.
Child & Teen BMI Calculator
Calculate BMI for children and teenagers aged 2 to 19. Because children's bodies change with age, the result must be interpreted using percentile growth charts.
Waist-to-Height Ratio Calculator
Calculate your waist-to-height ratio — a simple, powerful indicator of health risk based on a straightforward rule: keep your waist under half your height.
Child & Teen BMI Percentile Calculator
Calculate your child or teenager's BMI and see their exact BMI-for-age percentile using official CDC growth charts. For ages 2 to 20.
Women's Health
Ovulation Calculator
Find your most fertile days and estimated ovulation date.
Pregnancy Due Date Calculator
Calculate your estimated due date and track pregnancy milestones.
Period & Cycle Calculator
Predict your next period, fertile window and ovulation date based on your last period and cycle length. Track your menstrual cycle with confidence.
Pregnancy Weight Gain Calculator
Find your recommended total pregnancy weight gain based on your pre-pregnancy BMI, using Institute of Medicine guidelines for a healthy pregnancy.
Wellness & Lifestyle
Blood Alcohol Content (BAC) Calculator
Estimate your blood alcohol content based on drinks, body weight, sex and time. An educational estimate only — never use it to decide whether to drive.
Smoking Cost Calculator
See how much smoking really costs you over a day, month, year and decade. A clear look at the financial side of quitting — alongside the health benefits.
TSH Level Interpreter
Understand where your thyroid-stimulating hormone (TSH) result falls within general reference ranges.
Liver Enzyme (ALT) Interpreter
Understand where your ALT liver enzyme result falls within general reference ranges.
Ferritin Level Interpreter
Understand where your ferritin result falls within general reference ranges. Ferritin reflects the body's iron stores.
Vitamin B12 Level Interpreter
Understand where your vitamin B12 result falls within general reference ranges. B12 is essential for red blood cells and nerve health.
Folate Level Interpreter
Understand where your serum folate result falls within general reference ranges. Folate is essential for making red blood cells and for pregnancy.
Child & Teen BMI Percentile Calculator
Calculate your child or teenager's BMI and see their exact BMI-for-age percentile using official CDC growth charts. For ages 2 to 20.
Lab Results & Test Interpretation
BMR Calculator
Calculate your Basal Metabolic Rate (BMR) — the number of calories your body burns at complete rest to keep you alive. The foundation for understanding your energy needs.
HbA1c to Average Glucose Converter
Convert your HbA1c percentage to estimated average blood glucose (eAG), or work backwards from your average glucose to HbA1c. Shows results in both mmol/L and mg/dL.
Cholesterol Ratio Calculator
Calculate your total cholesterol to HDL ratio — a strong predictor of cardiovascular risk that doctors use alongside individual cholesterol numbers.
eGFR Calculator (Kidney Function)
Estimate your kidney function (eGFR) from your creatinine level, age and sex using the CKD-EPI 2021 equation used in clinical practice worldwide.
TSH Level Interpreter
Understand where your thyroid-stimulating hormone (TSH) result falls within general reference ranges.
Vitamin D Level Interpreter
Understand where your vitamin D blood result falls within general reference ranges.
Liver Enzyme (ALT) Interpreter
Understand where your ALT liver enzyme result falls within general reference ranges.
Haemoglobin Level Interpreter
Understand where your haemoglobin result falls within general reference ranges for anaemia screening.
Ferritin Level Interpreter
Understand where your ferritin result falls within general reference ranges. Ferritin reflects the body's iron stores.
Vitamin B12 Level Interpreter
Understand where your vitamin B12 result falls within general reference ranges. B12 is essential for red blood cells and nerve health.
Folate Level Interpreter
Understand where your serum folate result falls within general reference ranges. Folate is essential for making red blood cells and for pregnancy.