Free health calculators
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Body & NutritionBMICalculate your Body Mass Index with thresholds adjusted for your ethnicity — because health risk starts at different BMI levels across populations.Open calculatorDiabetesHbA1c ↔ eAGConvert your HbA1c percentage to an estimated average glucose (the number your glucometer shows), and back again.Open calculatorPregnancy & BabyDue dateEstimate your due date from your last period, conception date, or IVF transfer — with your current week and trimester.Open calculatorHeartBlood pressureFind out which category your blood pressure falls into, using the ACC/AHA 2017 guideline thresholds.Open calculatorMental HealthPHQ-9 (depression)A validated 9-question screen for depression severity. Private, takes two minutes, and not stored unless you choose to.Open calculatorKidney & LivereGFR (kidney)Estimate your kidney function with the 2021 race-free CKD-EPI equation — the standard recommended by kidney societies worldwide.Open calculatorBody & NutritionBMRThe calories your body burns at complete rest, just to keep your organs running.Open calculatorBody & NutritionTDEEThe total calories you burn in a day, including activity — your maintenance calories.Open calculatorBody & NutritionBody surface areaEstimate your body surface area — used clinically for drug and chemotherapy dosing.Open calculatorBody & NutritionIdeal body weightA reference weight from height and sex — originally developed for medication dosing, not personal goals.Open calculatorBody & NutritionWaist-hip ratioA simple measure of fat distribution and cardiometabolic risk — sometimes more telling than BMI.Open calculatorBody & NutritionBody fat %Estimate body fat percentage from a few tape measurements, using the US Navy formula.Open calculatorHeartMean arterial pressureThe average pressure in your arteries through one heartbeat — a key measure of organ perfusion.Open calculatorHeartCholesterol ratiosTurn your lipid panel into the ratios that best predict heart and metabolic risk.Open calculatorHeartHeart rate zonesYour five training heart-rate zones, from easy recovery to maximum effort.Open calculatorMental HealthSleep debtHow much sleep you owe yourself this week — and how to pay it back.Open calculatorNutritionCaffeine half-lifeSee how much caffeine is still in your system and when it will clear — so it doesn't wreck your sleep.Open calculatorKidney & LiverCreatinine clearanceEstimate creatinine clearance — the kidney measure many drug labels use for dosing.Open calculatorWomen's HealthOvulation predictorEstimate your ovulation day and fertile window from your last period and cycle length.Open calculatorWomen's HealthFertility windowYour most fertile days for trying to conceive, based on your cycle.Open calculatorWomen's HealthCycle predictorSee your next several periods and ovulation dates at a glance for planning.Open calculatorPregnancy & BabyPregnancy weight gainCheck whether your pregnancy weight gain is on track for your starting BMI, using IOM guidelines.Open calculatorNutritionProtein intakeHow much protein you need per day for your weight, activity and goal.Open calculatorNutritionWater intakeHow much fluid to aim for each day, adjusted for your weight, activity and climate.Open calculatorNutritionMacrosYour daily protein, carbs and fat targets for your calorie goal and diet style.Open calculatorNutritionCalorie goalThe daily calories to reach a target weight in your chosen timeframe — safely.Open calculatorHeartASCVD riskYour estimated 10-year risk of heart attack or stroke, using the ACC/AHA Pooled Cohort Equations.Open calculatorPregnancy & BabyChild growthSee where your baby's weight and length sit on the WHO growth standards for their age and sex.Open calculatorKidney & LiverFIB-4 (liver fibrosis)A simple blood-test score that estimates the likelihood of advanced liver fibrosis.Open calculatorKidney & LiverNAFLD fibrosis scoreEstimates the likelihood of advanced fibrosis specifically in fatty liver disease (NAFLD/NASH).Open calculatorMen's HealthCURB-65A clinical score for community-acquired pneumonia severity and where to treat it.Open calculatorHeartWells DVT scoreEstimates the pre-test probability of a deep vein thrombosis to guide next steps.Open calculatorElderlyMorse fall riskA widely-used inpatient score for a patient's risk of falling, with matched precautions.Open calculatorElderlyFRAIL scaleA quick five-question screen for frailty in older adults — and the window to reverse it.Open calculatorPregnancy & BabyAPGAR scoreThe standard 1- and 5-minute assessment of a newborn's condition at birth.Open calculatorMental HealthGAD-7 (anxiety)A validated 7-question screen for generalised anxiety over the past two weeks.Open calculatorMental HealthSleep quality (PSQI)The standard questionnaire for overall sleep quality over the past month, scored across seven components.Open calculatorKidney & LiverAUDIT (alcohol)The WHO's 10-question screen for risky and harmful drinking over the past year.Open calculatorPregnancy & BabyEPDS (postnatal)A validated 10-question screen for depression during pregnancy and after birth.Open calculatorMental HealthPerceived stressHow unpredictable, uncontrollable and overloaded you've found life in the past month.Open calculatorHeartCHA₂DS₂-VAScEstimates yearly stroke risk in non-valvular atrial fibrillation to guide anticoagulation.Open calculatorHeartHAS-BLEDEstimates 1-year major bleeding risk on anticoagulation — used alongside CHA₂DS₂-VASc.Open calculatorDiabetesIDRS (diabetes risk)A simple score, validated in Indian populations, for the risk of undiagnosed type 2 diabetes.Open calculatorDiabetesFINDRISCThe Finnish type-2 diabetes risk score — your 10-year risk and a prompt to act.Open calculatorDiabetesHOMA-IREstimates insulin resistance from fasting glucose and insulin — an early signal years before diabetes.Open calculatorHeartFramingham riskYour 10-year risk of general cardiovascular disease (heart attack, stroke, heart failure, PAD), from the Framingham study.Open calculatorHeartSCORE2 riskThe European Society of Cardiology's SCORE2 estimate of your 10-year risk of a first fatal or non-fatal cardiovascular event, by regional risk level.Open calculatorPregnancy & BabyPediatric fluidsDaily and hourly maintenance IV fluid requirements for a child by weight, using the Holliday-Segar 100-50-20 / 4-2-1 method.Open calculatorElderlyGCSScores level of consciousness from eye, verbal and motor responses (3–15) and gives the standard E-V-M documentation format.Open calculatorElderlyqSOFAA bedside 3-point screen (Sepsis-3) that flags patients with suspected infection who are at higher risk of a poor outcome.Open calculatorElderlyNIHSS screenAn 11-item educational version of the NIH Stroke Scale that estimates stroke severity. For learning and rough screening only — acute stroke is a time-critical emergency.Open calculatorKidney & LiverLab converterConvert common blood test results between conventional (US) units and SI (international) units — glucose, cholesterol, creatinine and 19 more.Open calculatorPregnancy & BabyPediatric doseEstimates common children's medication doses by weight and age — paracetamol, ibuprofen, amoxicillin, ORS and cetirizine. Always verify with a clinician.Open calculatorPregnancy & BabyChild BMI percentileCalculates a child's BMI and its percentile for age and sex using the CDC growth reference — the right way to read BMI in children and teens.Open calculatorKidney & LiverLab rangesLook up the usual adult reference range for 50+ common blood tests by sex — and optionally check where your value falls.Open calculatorPregnancy & BabyVaccine scheduleEnter a child's date of birth and country to see which routine vaccines are due, overdue, or coming up — a general guide to confirm with your pediatrician.Open calculatorPregnancy & BabyPregnancy drug safetyLook up the Australian TGA pregnancy category for common medicines, with trimester notes and safer alternatives — always confirm with your obstetrician.Open calculator
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