健康與健身

從身高與體重計算你的身體質量指數（BMI），並附 WHO 體重分類。

使用美國海軍圍度法，以公分為單位的頸圍、腰圍、臀圍與身高量測，估算你的體脂肪百分比。

使用 Mifflin-St Jeor 公式計算你的每日卡路里需求（TDEE），並取得減重、維持或增重的目標卡路里。

根據您的末次月經 (LMP) 得知您懷孕幾週幾天，並附上孕期階段、估算預產期與剩餘天數。

從你的年齡，以每分鐘心跳數計算你的最大心率與五個訓練區間，讓有氧運動更聰明。

使用廣為採用的 Devine 公式，從你的身高與性別以公斤求出你的理想體重，並附健康參考範圍。

使用 Epley 公式從一組訓練估算您的單次最大重量 (1RM)，並附上訓練負荷的百分比對照表 (95%–70%) 與目標反覆次數範圍。

根據您的末次月經與週期長度估算排卵日與易孕期，並推算您下一次預期的月經日期。免費的排卵與生育計算器。

逐週追蹤您的懷孕進度。輸入您的末次月經，即可得知目前的妊娠週數、孕期階段、估算預產期，以及懷孕進展程度。

使用內格萊氏法則 (Naegele's rule)，根據您的末次月經與週期長度估算懷孕預產期。查看妊娠週數、孕期階段與受孕日期。

計算你的腰臀比（WHR），並依世界衛生組織針對男性與女性的閾值查看你的健康風險分類。

根據你的體重與每日運動量估算你每天該喝多少水，以公升、毫升與杯顯示。

使用 Mifflin-St Jeor 公式估算你的基礎代謝率（BMR）與每日卡路里需求。

使用簡單而準確的 Mosteller 公式，從身高與體重以平方公尺計算體表面積（BSA）。

算出減重所需的每日熱量目標。輸入您的維持熱量 (TDEE) 與每週目標，即可得到安全的每日攝取量與赤字。

使用《身體活動綱要》(Compendium of Physical Activities) 的 MET 值估算運動所消耗的熱量。選擇一項活動，輸入您的體重與時間。

根據您的末次月經或預產期估算您的受孕日期，並提供數天範圍的可能受孕窗口。

使用 Boer 公式，從體重、身高與性別以公斤估算你的淨體重（LBM），並附近似的脂肪量。

將每日卡路里換算為碳水化合物、蛋白質與脂肪的公克數，適用於均衡、低碳或高蛋白飲食配比。

根據您的末次月經與平均週期長度，預測接下來 3 次月經的開始與結束日期，以及您估算的排卵日。

從距離與完成時間計算你以每公里分鐘數表示的跑步配速、以 km/h 表示的速度，以及每英里配速。

利用 90 分鐘的睡眠週期找出最佳就寢或起床時間。在週期之間醒來而非週期中途醒來，能讓您感覺更清爽、更不昏沉。

使用 Mifflin-St Jeor 公式，根據您的 BMR 與活動量估算每日總能量消耗 (TDEE)，並提供減重、維持與增重的熱量目標。

Calculate the Ankle-Brachial Index (ABI) from ankle and arm systolic pressures to screen for peripheral arterial disease (PAD).

Calculate your Army Combat Fitness Test (ACFT) score for all six events and see your total out of 600.

Calculate the urine albumin-to-creatinine ratio (ACR) from a spot urine sample to assess kidney health and CKD albuminuria category.

Estimate VO₂max from the Queens College Step Test 3-minute protocol — enter your 15-second post-exercise pulse count to get your aerobic fitness category.

Calculate the Apnea-Hypopnea Index (AHI) from a sleep study and classify sleep apnea severity per AASM guidelines.

Calculate the Absolute Neutrophil Count (ANC) from a CBC differential and classify neutropenia severity.

Calculate the APRI score (AST-to-Platelet Ratio Index) to estimate the probability of liver fibrosis and cirrhosis.

Estimate your blood alcohol concentration (BAC) using the Widmark formula. Enter drinks, weight, sex and time elapsed.

Calculate your Body Adiposity Index (BAI) — an estimate of body fat percentage from hip circumference and height, requiring no scale.

Analyse your basal body temperature (BBT) reading against your follicular baseline to detect the post-ovulation thermal shift and estimate cycle phase.

Calculate Biologically Effective Dose (BED) and EQD2 for any radiation therapy fractionation schedule using the linear-quadratic model.

Estimate Basal Energy Expenditure using the revised Harris-Benedict equation with optional stress and activity factors for clinical nutrition.

Score the Brief Interview for Mental Status (BIMS), a CMS MDS 3.0 cognitive screening tool used in nursing homes — three parts, total 0–15.

Calculate your Body Roundness Index (BRI) from height and waist circumference — a shape-based body fat estimate that outperforms BMI.

Calculate body surface area (BSA) in m² using the Mosteller, Du Bois, or Haycock formula — with a side-by-side comparison of all three.

Calculate the age-adjusted Charlson Comorbidity Index (CCI) from patient age and weighted comorbid conditions. Estimates 10-year survival probability.

Estimate creatinine clearance (CrCl) and kidney function stage using the Cockcroft-Gault equation from age, sex, weight, and serum creatinine.

Look up the NIH Dietary Reference Intake (RDA/AI) for protein, fibre, vitamins, and minerals by age and sex.

Calculate your estimated due date and current pregnancy week using Naegele's rule, adjusted for your personal cycle length.

Estimate your kidney filtration rate (eGFR) using the CKD-EPI 2021 race-free equation from serum creatinine, age, and sex.

Calculate your new ELO rating and points gained or lost after a match using the standard ELO formula for win, draw, or loss.

Calculate power output, calories burned and distance for a rowing ergometer workout from your 500 m split time using the Concept2 formula.

Estimate how long EtG (ethyl glucuronide) remains detectable in urine after alcohol consumption, based on drinks consumed and time elapsed.

Calculate your daily fat intake in grams from total calories and a fat percentage target, with protein, carb, and saturated fat breakdowns.

Calculate the Front of Center (FOC) percentage for an arrow using length and balance point — essential for tuning accuracy and stability in archery.

Calculate a premature baby's corrected (adjusted) age by subtracting weeks born early from their chronological age.

Calculate the Glycemic Load (GL) of a food from its Glycemic Index (GI) and carbohydrate content per serving.

Calculate the Glucose Infusion Rate (GIR) in mg/kg/min from dextrose concentration, infusion rate, and patient weight.

Calculate the Glasgow Coma Scale score from eye, verbal, and motor responses to assess level of consciousness.

Calculate the Hepatic Steatosis Index (HSI) from ALT, AST, BMI, sex and diabetes status to screen for non-alcoholic fatty liver disease.

Calculate ICC(1,1) or ICC(1,k) from one-way ANOVA mean squares to assess inter-rater or test-retest reliability, plus SEM and MDC₉₅.

Calculate the validated ICH Score (0–6) from GCS, hemorrhage volume, IVH, location and age to estimate 30-day mortality risk.

Calculate the International Normalized Ratio (INR) from PT, mean normal PT, and ISI — with therapeutic range interpretation for warfarin monitoring.

Calculate the Injury Severity Score (ISS) from AIS region scores to classify trauma severity from minor to unsurvivable.

Estimate LDL cholesterol from Total Cholesterol, HDL and Triglycerides using the Friedewald equation (mg/dL or mmol/L).

Calculate the MCA-PSV Multiple of Median (MoM) for fetal anemia screening using the Mari 2000 formula. For use with specialist guidance.

Convert any opioid dose to morphine milligram equivalents (MME/day) using CDC 2022 conversion factors.

Calculate the Neutrophil-to-Lymphocyte Ratio (NLR) from CBC counts — a rapid blood-test marker for systemic inflammation.

Calculate NNT, NNH, ARR, RRR, Relative Risk and Odds Ratio from control and experimental event rates.

Calculate the real-world noise reduction and protected dBA level from a hearing protector's NRR rating, using NIOSH or EPA methods.

Interpret a post-void residual (PVR) bladder scan — residual fraction, estimated capacity, and clinical severity category.

Calculate the Physiological Strain Index (PSI) from core body temperature and heart rate to quantify heat stress during exercise or occupational heat exposure.

Calculate the heart-rate-corrected QT interval (QTc) using Bazett, Fridericia, Framingham or Hodges formula — with prolongation risk interpretation.

Calculate your Resting Metabolic Rate (RMR) and TDEE using Mifflin-St Jeor or Katch-McArdle — choose based on whether you know your body fat %.

Calculate your bone density T-Score from a DXA scan BMD (g/cm²) and get a WHO classification: normal, osteopenia, or osteoporosis.

Calculate the IV Alteplase (tPA) dose for acute ischemic stroke: total dose, IV bolus, and 60-minute infusion by patient weight.

Calculate the Urea Reduction Ratio (URR) from pre- and post-dialysis BUN values to assess haemodialysis adequacy against the KDOQI ≥ 65 % target.

Calculate wound area reduction (WAR%) from initial and current wound dimensions to track healing progress and apply the validated 4-week 40% threshold.

Calculate how many eye-rest breaks you need based on the 20-20-20 rule: every 20 minutes look 20 feet away for 20 seconds.

Calculate the 4Ts score (Warkentin) to estimate the pre-test probability of heparin-induced thrombocytopenia (HIT) — 0–3 low, 4–5 intermediate, 6–8 high.

Calculate Jim Wendler's 5/3/1 powerlifting program working sets from your one-rep max — all four weeks including deload.

Calculate your 5K running pace in min/km and min/mile, speed in km/h and mph, and cumulative kilometre split times from a finish time.

Calculate your 6-minute walk test distance as a percentage of the age/sex/height/weight-predicted normal using the Enright & Sherrill equations.

Find the best bedtime or wake-up time by timing your sleep to complete full 90-minute cycles — wake refreshed instead of mid-cycle.

Calculate ABSI, a measure that captures abdominal obesity beyond BMI by combining waist circumference, height and weight.

Calculate the alveolar-arterial (A-a) oxygen gradient from arterial blood gas values to distinguish V/Q mismatch from hypoventilation.

Calculate the absolute eosinophil count (AEC) from WBC and eosinophil percentage and classify normal vs. eosinophilia severity.

Calculate arterial pH from bicarbonate and PaCO₂ using Henderson-Hasselbalch and classify the acid-base disturbance.

Score thyroid nodule ultrasound features using ACR TI-RADS 2017 to stratify malignancy risk and guide FNA decisions.

Estimate the financial and time cost of a daily habit: daily, monthly, and annual spend plus hours per year consumed by the habit.

Calculate the corrected (adjusted) age of a premature baby by subtracting weeks born early from the chronological age.

Calculate adjusted body weight (AdjBW) for drug dosing in obese patients using IBW + 0.4 × (ABW − IBW) — Devine formula for IBW.

Calculate CT adrenal washout percentages (APW and RPW) to help characterise adrenal incidentalomas as adenoma or non-adenoma.

Calculate the age-adjusted D-dimer threshold for PE exclusion. Patients ≥50 use age × 10 μg/L FEU instead of the standard 500 μg/L cut-off.

Calculate your US Air Force Physical Fitness Assessment (PFA) composite score for the 1.5-mile run, push-ups and abdominal circumference.

Calculate the albumin-to-globulin (A/G) ratio from serum albumin and total protein — useful for interpreting liver, kidney and immune function tests.

Calculate alcohol units in any drink from ABV and volume, and compare to UK weekly low-risk guidelines.

Calculate the modified Aldrete score to assess patient readiness for discharge from the Post-Anaesthesia Care Unit (PACU).

Calculate the Alvarado (MANTRELS) score to estimate the probability of acute appendicitis — 8 clinical and lab criteria, 0–10 scale.

Estimate median survival after an Alzheimer's disease diagnosis by age and sex, based on published cohort data. For educational use.

Estimate your anaerobic threshold heart rate and 5-zone training ranges from age and resting heart rate using the Karvonen Heart Rate Reserve method.

Calculate the Absolute Neutrophil Count (ANC) using only segmented neutrophils — excluding band cells — from a CBC differential and interpret the result.

Calculate the anion gap and albumin-corrected anion gap from serum Na⁺, Cl⁻, and HCO₃⁻ with interpretation guidance.

Calculate aortic valve area from cardiac output, heart rate, systolic ejection period, and mean pressure gradient using the Gorlin formula.

Calculate the APACHE II score from 12 physiological variables, age, and chronic health to estimate ICU severity and predicted hospital mortality.

Calculate your ape index (arm span minus height) and ape ratio (arm span ÷ height) — commonly used in rock climbing, swimming, and sports science.

Calculate the APGAR score for newborn assessment at 1 and 5 minutes after birth using the five standard criteria: Appearance, Pulse, Grimace, Activity, and Respiration.

Estimate vascular (arterial) age and 10-year coronary heart disease risk using the Framingham Point Score (NCEP ATP III, 2002).

Enter arterial pH, PaCO₂ and HCO₃⁻ to classify the acid-base disorder, verify Henderson-Hasselbalch consistency and assess compensation.

Calculate the AST/ALT (De Ritis) ratio to help differentiate alcoholic liver disease from viral hepatitis and NAFLD.

Complete the validated WHO 10-question AUDIT questionnaire, get your score (0–40), and see your risk zone with the recommended clinical intervention.

Screen for hazardous alcohol use with the validated 3-question AUDIT-C tool. Get your score (0–12) and see whether it meets the clinical positive-screen threshold.

Estimate your triathlon finish time from swim, bike and run paces and compare to typical age-group averages for sprint, Olympic, 70.3 and full Ironman.

Predict your baby's eye color probability from both parents' eye colors using a simplified Mendelian genetics model.

Calculate how much baby formula to prepare per feeding and per day based on your baby's weight.

Find your baby's weight and length percentile on WHO 2006 growth standards for boys and girls aged 0–24 months.

Find the recommended daily milk intake for your baby by age (0–24 months) and check whether their current intake is in the normal range.

Estimate how many days until you return to your normal routine after illness or surgery, based on your current rate of recovery.

Calculate the Barthel Index (0–100) to assess functional independence in daily activities — feeding, mobility, continence and more.

Calculate the BASDAI (Bath Ankylosing Spondylitis Disease Activity Index) score from 6 patient-reported questions on a 0–10 scale.

Calculate batting average for baseball (hits ÷ at-bats) or cricket (runs ÷ dismissals), with performance tier ratings.

Calculate cricket batting strike rate (runs per 100 balls) for T20, ODI and Test formats with benchmark ratings.

Screen for generalised joint hypermobility using the 9-point Beighton score. Answer 9 yes/no questions and see your score with clinical interpretation.

Estimate your bench press 1-rep max from any weight and rep count using five proven formulas (Epley, Brzycki, Mayhew and more).

Generate a complete bench press pyramid workout (ascending, descending or full) from your 1RM — with exact loads, reps and total training volume per session.

Convert between benzodiazepine doses using diazepam equivalents from the Ashton Manual. For reference only — not a substitute for clinical advice.

Score all 14 Berg Balance Scale items (0–4 each, max 56) and instantly see fall-risk category: high (0–20), moderate (21–40) or low (41–56).

Calculate the HCO₃ deficit in mEq for metabolic acidosis using the standard 0.4 × weight × (target − actual) formula.

Calculate the correct bicycle chain length in links and millimetres from chainstay length and chainring/cassette size using the Park Tool formula.

Find the pedalling cadence needed to reach a target cycling speed for any gear and wheel size — with a cadence–speed curve.

Calculate your cycling speed from pedalling cadence, gear ratio and wheel circumference — see which RPM zone you are in.

Calculate cycling gear ratio, gear development (m/rev) and gain ratio from chainring teeth, cog teeth, wheel circumference and crank length.

Calculate your average cycling speed and pace (min/km) from distance and time — with projected finish times for common cycling distances.

Find the right road, mountain or city bike frame size from your inseam and height — with saddle height and size category.

Calculate average cycling speed in km/h and mph, pace per km and mile, from ride distance and time.

Estimate how many years of life regular cycling adds based on the 2016 PLOS Medicine meta-analysis — enter weekly ride time and intensity.

Calculate the total, annual, and daily cost of any birth control method from monthly fees and any one-time upfront cost.

Estimate a newborn's birth weight percentile by gestational age and sex using approximate Fenton 2013 / INTERGROWTH-21st reference ranges.

Calculate the Bishop score for cervical ripeness before labour induction — scoring dilation, effacement, fetal station, consistency and position (0–13).

Estimate bladder volume from 3-D ultrasound measurements (length, width, depth) using the validated ellipsoidal formula V = 0.52 × L × W × H.

Find which blood types are compatible for donation and transfusion based on ABO and Rh factor — for whole blood / red blood cells.

Estimate acute blood loss from haemoglobin drop using the Gross formula and classify severity by ATLS haemorrhage class.

Calculate beta-hCG doubling time from two blood test results to assess early pregnancy viability. Normal: doubles every 48–72 hours.

Enter systolic and diastolic readings to get AHA/ACC 2017 blood pressure classification, mean arterial pressure, and pulse pressure.

Convert blood glucose between mg/dL and mmol/L, classify fasting or post-meal readings per ADA 2024, and estimate HbA1c.

Find out which blood types you can donate to or receive from, and see possible child blood types from two parents.

Estimate total blood volume in litres using Nadler's equation from height, weight and sex — used clinically before surgery or transfusion.

Calculate BMI-for-age percentile for children and teens aged 2–20 using CDC 2000 growth chart LMS method, with weight category.

Calculate BMI for men with WHO weight category, healthy weight range for your height, and estimated body fat % using the Deurenberg formula.

Calculate BMI for women using the standard WHO formula and optionally assess cardiovascular risk from waist circumference using WHO women's thresholds (80/88 cm).

Calculate BMI for children and teenagers aged 2–20 using CDC age- and sex-adjusted percentile categories: underweight, healthy, overweight, or obese.

Calculate pre-pregnancy BMI and personalised gestational weight-gain targets using IOM 2009 guidelines for single and twin pregnancies.

Calculate a child's BMI-for-age percentile and z-score using CDC 2000 LMS growth charts for ages 2–20, with bell-curve visualisation.

Find the target weight needed to reach a goal BMI and estimate how many weeks it will take at different daily calorie deficits.

Calculate Basal Metabolic Rate using the original (1918) or revised (1984 Roza–Shizgal) Harris-Benedict equation, then multiply by an activity factor to get TDEE.

Calculate Basal Metabolic Rate using the Katch-McArdle formula — the only BMR equation based on lean body mass rather than total weight, making it more accurate for athletes.

Calculate the BODE index for COPD severity using BMI, FEV₁%, mMRC dyspnea scale and 6-minute walk distance.

Determine your body frame size (small, medium or large) from height and wrist circumference using the height-to-wrist ratio.

Find your body shape (hourglass, pear, apple, rectangle, inverted triangle) from bust, waist and hip measurements.

Estimate total body water (TBW) in litres and as a percentage of body weight using the Watson formula for men and women.

Calculate your bowling average from game scores — see your high game, low game and pin total across any number of sessions.

Calculate the Braden Scale score to assess a patient's risk of pressure injuries (bedsores) across six clinical subscales.

Estimate breast cancer recurrence risk and 10-year survival using the validated Nottingham Prognostic Index (NPI) from tumour size, grade and node stage.

Estimate your 5-year breast cancer risk using a simplified Gail model based on age, family history, menstrual history and prior biopsies.

Find the correct breast pump flange (shield) size from your nipple diameter — the right fit improves milk output and comfort.

Calculate how many extra calories you need while breastfeeding using IOM guidelines and the Mifflin-St Jeor equation for your TDEE.

Estimate VO₂max and METs from a Bruce Protocol treadmill exercise test using the Bruce (1973) and McConnell & Clark (1987) regression equations.

Calculate the BUN-to-creatinine ratio from a metabolic panel to help distinguish pre-renal, renal, and post-renal azotemia.

Estimate calories burned doing burpees based on body weight, repetitions, and pace — using MET values from the Compendium of Physical Activities.

Estimate the caffeine remaining in your body using exponential decay with a 5.7-hour average half-life.

Screen for alcohol use disorder using the validated 4-question CAGE questionnaire. A score of 2 or more warrants professional evaluation.

Calculate daily calories for weight loss, maintenance or muscle gain using the Mifflin-St Jeor BMR equation and your activity level.

Estimate how hot a parked car gets after any number of minutes in the sun, with danger-level rating for children, pets and the elderly.

Calculate daily carbohydrate, protein and fat grams from a calorie target and macro split percentage.

Calculate carboplatin chemotherapy dose using the Calvert formula and Cockcroft-Gault creatinine clearance estimate.

Calculate cardiac index (CI) and cardiac output (CO) from heart rate, stroke volume and body surface area using the Mosteller formula.

Calculate cardiac output (CO) and cardiac index (CI) from heart rate and stroke volume using CO = HR × SV.

Calculate the Crohn's Disease Activity Index (CDAI) from stool count, pain, well-being, labs and physical findings. Classifies remission to severe disease.

Calculate the modified Centor (McIsaac) score to estimate Group A strep throat probability and guide antibiotic decisions.

Calculate cerebral perfusion pressure (CPP = MAP − ICP) from systolic BP, diastolic BP and intracranial pressure, with clinical interpretation.

Calculate the CHA₂DS₂-VASc score to estimate annual ischaemic stroke risk in atrial fibrillation and guide anticoagulation decisions.

Estimate a child's height percentile by age and sex using approximate CDC 2000 growth chart reference values (ages 2–20).

Find a child's weight percentile and Z-score using the WHO Growth Reference (2006) for boys and girls aged 0–60 months.

Calculate the Child-Pugh score and class (A/B/C) for liver cirrhosis severity from bilirubin, albumin, INR, ascites, and encephalopathy.

Calculate your key cholesterol ratios (TC/HDL, LDL/HDL, TG/HDL) and see how they map to cardiovascular risk ranges.

Convert cholesterol and triglyceride readings between mmol/L (EU/UK) and mg/dL (US) for TC, HDL, LDL and TG.

Calculate the daily, monthly, annual, and lifetime cost of smoking, total cigarettes, and pack-years from your smoking habits.

Find the best times to wake up based on 90-minute sleep cycles so you rise feeling refreshed, not groggy.

Score alcohol withdrawal severity using the validated CIWA-Ar scale (0–67). Assesses 10 symptom domains.

Estimate ovulation dates and fertile window during a Clomid (clomiphene) cycle using the days 3–7 or 5–9 protocol.

Estimate your conception date from your baby's birth date by working backward 266 days (38 weeks). Shows the fertile window and estimated LMP.

Correct serum calcium for low or high albumin using the Payne formula: Ca_corrected = Ca_measured + 0.8 × (4.0 − albumin).

Calculate albumin-corrected serum magnesium to reveal true Mg status in patients with low albumin (hypoalbuminemia).

Convert between corticosteroid doses using standard anti-inflammatory equivalency: prednisone, dexamethasone, hydrocortisone and more.

Estimate the probability that at least one infectious person is present at a gathering, using local prevalence and an ascertainment factor for unreported cases.

Estimate historical COVID-19 infection fatality rate by age, comorbidities and vaccination status using peer-reviewed IFR data.

Estimate creatinine clearance (CrCl) using the Cockcroft-Gault formula and classify kidney function by CKD stage.

Determine whether a cricket team can enforce the follow-on based on first-innings scores and match duration under ICC Playing Conditions.

Convert a crown-rump length (CRL) in mm to gestational age in weeks and days using the Robinson & Fleming formula.

Calculate the CURB-65 score to estimate 30-day mortality risk in community-acquired pneumonia and guide admission decisions.

Estimate your 10-year cardiovascular disease risk using the Framingham Risk Score from cholesterol, blood pressure, age, sex, smoking and diabetes.

Calculate whether a cycling breakaway will survive to the finish line based on gap, remaining distance, and breakaway vs peloton speed.

Calculate your 5 cycling heart rate training zones from max HR — with optional Karvonen (heart-rate-reserve) zones if you enter your resting HR.

Calculate all 7 Coggan cycling power training zones from your FTP (Functional Threshold Power) in watts and W/kg.

Calculate the watts required to cycle at a given speed and gradient using a physics-based model of aerodynamic drag, rolling resistance, gravity and drivetrain loss.

Calculate how much protein you need per day based on body weight and goal — maintain weight, endurance sport, muscle building or weight loss. Based on ISSN 2017 guidelines.

Calculate the DAPT score (Yeh et al. 2016) to guide the duration of dual antiplatelet therapy after PCI. Score ≥ 2 favours prolonged DAPT.

Calculate the Duke Activity Status Index (DASI) score to estimate functional capacity in METs and VO₂ peak from 12 self-reported activity questions.

Calculate anatomical or physiological pulmonary dead space, VD/VT ratio, alveolar ventilation and minute ventilation.

Calculate the Denver HIV Risk Score to identify patients who may benefit from HIV screening. Score ≥ 4 recommends testing.

Estimate your 10-year risk of developing type 2 diabetes using the validated FINDRISC screening score (Lindström & Tuomilehto, 2003).

Classify DKA severity and compute anion gap, corrected sodium, Winter's pCO₂, and effective osmolality from blood glucose, pH, and electrolytes.

Calculate the ISTH overt DIC score from platelets, D-dimer, PT prolongation, and fibrinogen — educational use only.

Assess your dietary risk across 6 WHO-aligned food factors — fruits & veg, whole grains, meat, sugar, fish, and sugary drinks.

Calculate the recommended DIN binding release setting based on weight, boot sole length, skier type and age (ISO 11088 simplified).

Calculate the exact sugar and salt amounts to make a homemade isotonic sports drink. Set your carbohydrate % and sodium target per batch.

Calculate the International Prognostic Index (IPI) and Revised IPI (R-IPI) for diffuse large B-cell lymphoma prognosis.

Calculate calories burned and miles walked from daily dog walks. Enter weight, pace, duration and frequency to see weekly and yearly fitness totals.

Calculate cardiac output and cardiac index from Doppler echocardiography: LVOT diameter, VTI, and heart rate using the stroke-volume method.

Calculate your archery draw length from arm span using the AMO/ATA standard formula. Get the right bow fit first time.

Calculate the IV infusion drip rate in drops per minute (gtts/min) and flow rate (mL/hr) from volume, time and drop factor.

Calculate how many drops per minute to count when regulating a gravity IV drip set, from the ordered mL/hr rate and drop factor.

Calculate the revised D/L target in cricket when overs are lost to rain. Uses the published 2002 Duckworth-Lewis resource model coefficients.

Screen for drug use disorders with the validated 11-question DUDIT tool. Get your score (0–44) and see if it meets the clinical positive-screen threshold.

Estimate your functional capacity in METs from the 12-item Duke Activity Status Index questionnaire — used in cardiac risk assessment.

Calculate the vertical jump you need to dunk a basketball based on your height, standing reach and rim height.

Estimate your electric bike range from battery size, speed, rider weight, terrain and assist level using physics-based energy modelling.

Calculate the EASI score for atopic dermatitis severity across four body regions with intensity and area scoring.

Convert ECG grid boxes to seconds or milliseconds at 25 or 50 mm/s, and calculate heart rate from the RR interval box count.

Calculate heart rate in bpm from an ECG strip using the RR interval, the 1500 rule, or the 6-second strip count method.

Calculate your Estimated Energy Requirement (EER) using the IOM 2002 DRI equations for adults, with adjustments for activity level, pregnancy, and lactation.

Estimate how many mature oocytes to freeze to achieve a target probability of at least one live birth, based on age-group success rates from published fertility data.

Estimate calories burned on an elliptical trainer from body weight, session duration and effort level using MET values.

Calculate the EORTC recurrence (0–17) and progression (0–23) scores for non-muscle-invasive bladder cancer per Sylvester 2006.

Score the Edinburgh Postnatal Depression Scale (EPDS) across 10 questions. Threshold ≥ 10 flags possible perinatal depression.

Calculate your Epworth Sleepiness Scale (ESS) score across 8 everyday situations and classify daytime sleepiness severity (0–24).

Calculate a pitcher's Earned Run Average (ERA): earned runs allowed per 9 innings pitched, with MLB context bands.

Calculate effective regurgitant orifice area using the PISA method to grade mitral regurgitation severity from echocardiographic measurements.

Estimate standing height in bedridden or wheelchair-bound patients from knee height and age using the Chumlea 1985 formula.

Convert HbA1c (%) to estimated average glucose (eAG) in mg/dL or mmol/L using the ADA-validated Nathan 2008 equation.

Calculate endotracheal tube (ETT) internal diameter and insertion depth for paediatric patients by age (Motoyama formula) or neonatal weight.

Compare actual pregnancy weight gain with IOM 2009 recommendations by BMI category and gestational week — assess if gain is on track, below or above the guideline range.

Plan your exclusive pumping schedule: track daily milk output, compare with your baby's estimated needs, and see surplus, session timing and weekly totals.

Determine your face shape — oval, round, square, heart, diamond, or oblong — from four simple measurements.

Complete the validated 6-question Fagerström Test and get your nicotine dependence score (0–10) with clinical guidance.

Estimate the probability of a false negative pregnancy test at any DPO based on hCG levels and test sensitivity.

Find your fat-burning heart rate zone (60–70% of max HR) and all five training zones using three validated max HR formulas.

Score the validated 9-item Fatigue Severity Scale (FSS). A mean score ≥ 4 indicates clinically significant fatigue.

Calculate the Fractional Excretion of Sodium (FENa) from urine and plasma sodium and creatinine to differentiate pre-renal from intrinsic acute kidney injury.

Estimate the monthly and cumulative probability of conception by female age, based on published fecundability research and SART IVF data.

Calculate fetal weight percentile and SGA/AGA/LGA classification by gestational age using Hadlock 1991 log-normal reference standards.

Calculate fractional excretion of urea (FEUrea) to differentiate prerenal AKI from intrinsic renal injury — especially useful when the patient is on diuretics.

Calculate the FEV1/FVC ratio from spirometry, determine obstructive vs restrictive patterns, and compare to ERS 1993 predicted values by age, sex, and height.

Calculate your Fat-Free Mass Index (FFMI) and normalised FFMI from weight, height, and body fat percentage, with natural physique classification.

Calculate the FIB-4 index from age, AST, ALT and platelet count to assess risk of advanced liver fibrosis non-invasively.

Calculate your recommended daily fiber intake by age and sex, compare it to your current intake, and find high-fiber foods to close the gap.

Calculate the Finnegan Neonatal Abstinence Syndrome (NAS) score across 21 CNS, metabolic/vasomotor/respiratory, and GI signs to guide treatment decisions for neonatal opioid withdrawal.

Calculate your daily EPA and DHA omega-3 intake from fish oil supplements and see how it compares to AHA and FDA recommendations.

Estimate the weight of a fish from its length and girth using the standard sport-fishing formula W = (L × G²) / 800.

Calculate how many yards of fishing line fit on a reel from spool OD, core diameter, width and line diameter.

Calculate the Fractional Excretion of Phosphate (FE_PO4 / FPCT) to assess renal tubular phosphate handling and detect phosphate wasting or retention.

Screen for frailty using the validated 5-item FRAIL Scale: fatigue, resistance, ambulation, illnesses, and weight loss.

Estimate 10-year cardiovascular disease risk using the NCEP ATP III Framingham Point Score (2001 tables).

Estimate free and bioavailable testosterone from total testosterone, SHBG and albumin using the Vermeulen 1999 quadratic formula.

Calculate expected fundal height from gestational age, or estimate gestational age from a fundal height measurement using McDonald's rule (1 cm per week, 20–36 weeks).

Score the GAD-7 questionnaire to screen for generalized anxiety disorder severity: minimal, mild, moderate, or severe.

Convert raw game, quiz or test scores to a percentage and US letter grade, with optional penalty deductions and bonus point adjustments.

Estimate weight loss outcomes after gastric sleeve surgery based on median EWL% from published clinical research.

BMI calculator with geriatric-adjusted cut-offs for adults aged 60+. Healthy range shifts to 22–27 to reduce malnutrition risk in older adults.

Estimate glomerular filtration rate (eGFR) using the 2021 CKD-EPI race-free formula from serum creatinine, age and sex. Shows KDIGO CKD stage.

Calculate the glycemic load (GL) of any food from its Glycemic Index and net carbohydrates per serving to assess blood-sugar impact.

Calculate a goalie's save percentage (SV%) and Goals Against Average (GAA) from shots faced and goals allowed in hockey or soccer.

Calculate mitral, aortic or tricuspid valve area using the Gorlin formula from cardiac output, heart rate, filling period and mean pressure gradient.

Apply the ACR/EULAR 2015 gout classification criteria: score joint pattern, clinical features, serum urate, and imaging to classify gout.

Calculate the GRACE score for acute coronary syndrome to estimate in-hospital mortality risk from age, BP, HR, creatinine, Killip class and ECG findings.

Estimate gut microbiome-supportive lifestyle score based on fiber intake, plant variety, fermented foods, antibiotic use and sleep quality.

Calculate your half marathon pace per km and per mile, speed, and cumulative split times from a finish time.

Calculate doses per bottle, cost per application and supply needs — or get a DIY recipe to dilute alcohol to the WHO-recommended 60–80% concentration.

Estimate your subjective well-being with a PERMA-based composite score across positive emotions, engagement, relationships, meaning, accomplishment and lifestyle factors.

Calculate the HAS-BLED score to estimate major bleeding risk in patients with atrial fibrillation receiving anticoagulant therapy.

Check if your hCG level is within the typical range for your week of pregnancy. Reference values from published clinical data.

Convert between hematocrit (HCT) and hemoglobin (HGB) using the standard MCHC formula, and check against normal ranges for men and women.

Calculate a baby or toddler's head circumference percentile using WHO Child Growth Standards for boys and girls aged 0–24 months.

Estimate median survival with heart failure by NYHA functional class, ejection fraction, and age — based on published cohort data.

Calculate heart rate recovery (HRR) after exercise and assess cardiovascular fitness — an abnormal HRR is linked to elevated mortality risk.

Calculate the HEART score to stratify chest pain patients for Major Adverse Cardiac Events (MACE). For use by healthcare professionals.

Convert HbA1c % to estimated average glucose (eAG) in mg/dL and mmol/L using the ADA formula, with diabetes risk category.

Calculate a women's heptathlon total score using the official IAAF 1985 scoring tables for all seven events.

Estimate calories burned hiking from body weight, distance, elevation gain, speed and pack weight.

Estimate hiking time using Naismith's Rule with Langmuir's descent correction and a fitness-level multiplier.

Calculate HOMA-IR and beta-cell function (HOMA-β) from fasting glucose and fasting insulin to screen for insulin resistance.

Calculate the theoretical hull speed of any displacement vessel from waterline length: results in knots, km/h, and mph with a Froude number.

Estimate punch force in newtons, kgf, and lbf from body weight and fist speed using a biomechanical effective-mass model.

Estimate intracerebral hemorrhage volume from CT scan measurements using the validated ABC/2 formula. Enter diameters and slice count to get mL volume.

Calculate your TDEE-based daily calorie target and flexible macro breakdown (protein, fat, carbs) using the IIFYM method.

Find your implantation window (days 6–12 after ovulation) and see where today falls within it.

Calculate the incidence rate (new cases per 100,000 or any multiplier), incidence proportion and attack rate from case count and population.

Convert any IQ score to a percentile rank and population frequency using the normal distribution (mean 100, SD 15, Wechsler scale).

Estimate total body iron deficit in mg using the Ganzoni formula: weight × (target Hb − actual Hb) × 2.4 + iron stores.

Calculate the cumulative isotretinoin dose (mg/kg) for an acne treatment course and compare it to the 120–150 mg/kg target range.

Calculate IV infusion flow rate in mL/hr and drip rate in drops/min from total volume, infusion time and drop factor.

Estimate calories burned jumping rope by body weight, duration and pace. Uses MET values from the Compendium of Physical Activities.

Calculate target heart rate and all 5 Karvonen training zones from age, resting HR and target intensity. Uses the Heart Rate Reserve method.

Calculate your daily keto calorie target with net carb, protein, and fat goals in grams using the Mifflin-St Jeor BMR formula.

Estimate kidney stone volume and spontaneous passage probability from imaging dimensions (mm).

Find the right kite size for your weight and wind speed, estimate aerodynamic lift force, and calculate calories burned during a kiteboarding session.

Calculate single-pool Kt/V (Daugirdas second-generation formula) to assess haemodialysis adequacy against the KDOQI ≥ 1.2 target.

Apply Light's criteria to classify a pleural effusion as exudate or transudate using pleural fluid and serum protein and LDH values.

Calculate the Lille model score to predict corticosteroid response at day 7 in severe alcoholic hepatitis and guide continuation of therapy.

Calculate the weight-based maximum safe dose and corresponding volume for local anesthetic agents — lidocaine, bupivacaine, ropivacaine and more.

Calculate the LRINEC score from six routine lab values to assess the probability of necrotizing fasciitis, with instant risk stratification.

Calculate the annual cost of lubricating a treadmill or exercise machine based on weekly usage, application interval, and lubricant price.

Estimate pack-years, check USPSTF LDCT screening eligibility, and see your qualitative lung-cancer risk category as a current or former smoker.

Predict your FVC and FEV1 lung volumes using validated Quanjer 1993 spirometry reference equations for your age, height, and sex.

Calculate the Volume Doubling Time (VDT) of a pulmonary nodule from two CT diameters and the scan interval to assess malignancy risk.

Calculate your luteal phase start, estimated ovulation date, fertile window, and next period date from your cycle length and luteal phase duration.

Calculate Left Ventricular Mass Index (LVMI) from echocardiographic measurements using the ASE Devereux formula and DuBois BSA to detect LV hypertrophy.

Calculate absolute lymphocyte count (ALC) from WBC and lymphocyte percentage, with normal range classification.

Calculate Maddrey's Discriminant Function (MDF) to assess severity and short-term mortality risk in alcoholic hepatitis.

Predict your 5K, 10K, half-marathon and marathon finish times from a 1-mile time trial using Jeff Galloway's Magic Mile method.

Find your personal "magic number" — the days needed to reach a goal weight — from your calorie deficit using the 7,700 kcal/kg fat rule.

Find your daily maintenance calories (TDEE) using the Mifflin–St Jeor formula — plus cut and bulk targets.

Calculate paediatric maintenance IV fluid rates using the Holliday-Segar method: daily mL and hourly mL/hr by weight.

Calculate the pace per kilometre and per mile needed to finish a marathon in your goal time, with even-effort split projections for 5K, 10K, the half, and the finish.

Compare the estimated protection offered by different mask types — cloth, surgical, KN95, N95 — versus wearing no mask.

Estimate your maximum heart rate by age using Fox (220−age), Tanaka and Gellish formulas, plus all five training zones in bpm.

Convert micrograms (mcg) to International Units (IU) for vitamins A, D and E using official FDA conversion factors.

Log food items and their calorie counts to total a meal and compare against your daily calorie target.

Calculate mean airway pressure (MAP) in mechanically ventilated patients from PIP, PEEP, inspiratory time, and respiratory rate.

Calculate mean arterial pressure from systolic and diastolic readings. MAP = DBP + (SBP − DBP) / 3.

Calculate mean sac diameter from three ultrasound measurements and estimate gestational age using the MSD + 30 days formula.

Estimate your cumulative effective radiation dose from medical imaging (X-rays, CT scans, PET scans) and compare it to background radiation.

Calculate the three best times to take a medication prescribed three times a day (TID), spaced evenly from your first dose.

Calculate the MELD and MELD-Na score for end-stage liver disease from bilirubin, INR, creatinine and sodium.

Calculate the Mentzer Index (MCV ÷ RBC) to help differentiate thalassemia trait from iron deficiency anaemia in microcytic cases.

Calculate weekly MET-minutes of physical activity and compare against WHO guidelines. Enter activity, minutes per session, and sessions per week.

Check how many of 5 NCEP ATP III metabolic syndrome criteria are met: abdominal obesity, triglycerides, HDL, blood pressure, and fasting glucose.

Apply CHAARTED volume and LATITUDE risk classifications for mHSPC, or score unfavorable prognostic factors for mCRPC — educational reference tool.

Calculate the Modified Early Warning Score (MEWS) from five vital signs to detect patient deterioration and trigger timely escalation.

Calculate your 8-hour time-weighted average (TWA) for airborne mica dust and Hazard Quotient against the NIOSH REL of 3 mg/m³.

Check whether your daily vitamin or mineral intake meets the RDA and stays below the upper limit — with status and a visual scale.

Calculate the MIPI score for Mantle Cell Lymphoma risk stratification using age, ECOG PS, LDH/ULN and WBC.

Calculate mitral valve area (MVA) from Pressure Half-Time using the Hatle formula (MVA = 220 / PHT) with ACC/AHA severity classification.

Convert blood glucose, cholesterol, triglycerides and other lab values between mmol/L and mg/dL instantly.

Calculate the Morse Fall Scale (MFS) score to classify fall risk in hospitalised patients across 6 validated criteria.

Calculate the crude mortality rate per 1 k / 10 k / 100 k population and the case fatality rate from deaths, population, and confirmed cases.

Calculate the NAFLD Fibrosis Score (NFS) to estimate likelihood of advanced liver fibrosis (F3–F4) in non-alcoholic fatty liver disease.

Estimate your US Navy Physical Readiness Test (PRT) composite score for push-ups, curl-ups and the 1.5-mile run by age group and gender.

Calculate the NEDOCS score to quantify emergency department overcrowding. Enter current ED census data and see the validated 0–200 crowding level.

Calculate net carbs by subtracting fiber and sugar alcohols from total carbohydrates. Supports full and half sugar-alcohol deduction methods for keto and low-carb tracking.

Assess neonatal jaundice risk using the Bhutani hour-specific nomogram: enter TSB, postnatal age, and gestational age to identify the risk zone and estimated phototherapy threshold.

Calculate the official NFL passer rating (quarterback rating) from completions, attempts, passing yards, touchdowns and interceptions.

Calculate the NIH Stroke Scale score (0–42) across all 15 items to quantify stroke severity. For clinical reference only.

Predict sound levels at any distance from a noise source and check WHO community risk and NIOSH occupational exposure limits.

Estimate nuchal translucency MoM from NT measurement and CRL, with gestational age and risk category — for educational reference only.

Calculate OBP, slugging percentage and OPS from hits, walks, at-bats and other batting stats using official MLB formulas.

Convert between opioids using CDC 2022 MME factors and a configurable cross-tolerance reduction (25–50%) for safe opioid rotation.

Calculate your OST (Osteoporosis Self-Assessment Tool) index to estimate low bone density risk in postmenopausal women using weight and age.

Check if you are overweight using BMI, see your healthy weight range for your height, and find how much to lose or gain.

Calculate the oxygenation index from MAP, FiO₂, and PaO₂ to assess severity of respiratory failure.

Calculate your running or walking pace (min/km or min/mile) from distance and time, with race finish time predictions.

Calculate pack-years of smoking history from cigarettes per day and years smoked, with risk category indication.

Calculate the Padua Prediction Score to assess venous thromboembolism (VTE) risk in acutely ill hospitalised patients.

Calculate the PaO₂/FiO₂ ratio (Horowitz index) from arterial blood gas values and classify ARDS severity using the Berlin 2012 definition.

Calculate IV fluid requirements for burn patients using the Parkland formula (4 mL/kg/%TBSA) or Modified Brooke formula, with first-8-hour and next-16-hour rates.

Calculate your predicted peak expiratory flow rate (PEFR) by age, height and sex using the Nunn & Gregg (1989) reference equations, and find your asthma traffic-light zone.

Calculate the Pearl Index — the number of unintended pregnancies per 100 woman-years — to measure the effectiveness of a contraceptive method.

Apply the PECARN pediatric head CT decision rule to stratify children with minor blunt head trauma into Low, Intermediate, or High risk for clinically important brain injury.

Compare a child's blood pressure to age- and sex-specific percentile thresholds from the NHLBI 4th Report and AAP 2017 CPG.

Estimate a child's total blood volume (EBV) from body weight and age group using established mL/kg reference values.

Score the Epworth Sleepiness Scale (ESS) for adolescents to quantify daytime sleepiness. Scores above 10 suggest excessive daytime sleepiness.

Estimate the glomerular filtration rate in children using the Bedside Schwartz 2009 or Classic Schwartz formula from height and serum creatinine.

Calculate the packed red blood cell (pRBC) transfusion volume for a child from current and target haemoglobin, body weight, and age group.

Apply the 8-item PERC rule to safely exclude pulmonary embolism without D-dimer testing in low pre-test probability patients.

Calculate the Progesterone-to-Estradiol (PG/E2) ratio from serum levels. Supports ng/mL, nmol/L and pg/mL inputs with luteal-phase interpretation.

Score the PHQ-9 depression questionnaire (0–27) to assess depressive symptom severity from minimal to severe.

Calculate EROA and regurgitant volume for mitral regurgitation by the PISA (Proximal Isovelocity Surface Area) echocardiographic method.

Calculate serum/plasma osmolality from sodium, glucose and BUN using the Smithline–Gardner formula, with osmol gap.

Estimate plasma volume from height, weight and hematocrit using the Nadler formula for total blood volume.

Track your Pokémon GO egg hatching progress and buddy candy earnings by distance walked. Find how far left to reach your candy goal.

Calculate your Ponderal Index (PI = kg/m³) — a body-weight index that adjusts for height more accurately than BMI for tall or short individuals.

Calculate the minimum room size for a pool or snooker table — 7 ft to 12 ft — with full cue clearance on every side.

Estimate the true probability of pregnancy after a positive home test using test sensitivity, specificity and your prior likelihood (Bayes theorem).

Understand what "3 weeks pregnant" really means for a pregnancy test, estimate hCG levels, and find out if a test would likely be positive.

Estimate hCG levels by days past ovulation and see whether a home pregnancy test is likely to be positive or negative.

Find your recommended gestational weight gain range by pre-pregnancy BMI, track weekly targets, and see if your current gain is on track — based on IOM 2009 guidelines.

Find your recommended total pregnancy weight gain by pre-pregnancy BMI using IOM 2009 guidelines, with trimester breakdown and weekly rate.

Calculate when your prescription runs out, how many pills you have left today, and the recommended date to request a refill.

Calculate the urine protein-to-creatinine ratio (PCR) from a spot sample — estimates 24-hour proteinuria without a timed collection.

Calculate PSA density (PSAD) from serum PSA and prostate volume — helps distinguish cancer from benign prostatic enlargement.

Calculate PSA doubling time from two serial PSA readings — indicates rate of prostate cancer progression and guides treatment decisions.

Calculate the pulmonary-to-systemic blood flow ratio (Qp:Qs) from cardiac catheterisation oxygen saturations to quantify intracardiac shunts.

Calculate the quick SOFA (qSOFA) score to screen for sepsis risk at the bedside. Score ≥ 2 warrants urgent evaluation.

Plan home workouts during quarantine: enter days, daily exercise minutes and intensity to see total calories burned and WHO compliance percentage.

Calculate the Quantitative Insulin Sensitivity Check Index (QUICKI) from fasting insulin and glucose to assess insulin resistance.

Predict finishing times at any running distance using Pete Riegel's formula T₂ = T₁ × (D₂/D₁)^1.06 — enter one known race result.

Enter your current race time and target improvement percentage to find your goal time, time to save, and the new pace required to hit it.

Calculate the Rate-Pressure Product (RPP = HR × SBP) to estimate myocardial oxygen demand and cardiac workload during rest or exercise.

Calculate MCV, MCH and MCHC red blood cell indices from hemoglobin, hematocrit and RBC count. Useful for classifying anaemia type.

Estimate peri-operative major adverse cardiac event (MACE) risk using the Revised Cardiac Risk Index (Lee Index, 1999) — 6 binary risk factors.

Estimate body fat percentage with the Relative Fat Mass formula — a simple height-to-waist ratio method shown to outperform BMI.

Estimate how much REM sleep you get each night based on total sleep duration, using 90-minute cycle averages for each sleep stage.

Calculate the corrected reticulocyte count (CRC) and reticulocyte production index (RPI) to assess bone marrow response in anemia.

Estimate the pre-test probability of pulmonary embolism (PE) using the Revised Geneva Score — 8 clinical variables, no arterial blood gas required.

Calculate the Revised Trauma Score from GCS, systolic BP and respiratory rate — triage and predict survival probability after major trauma.

Calculate the Rapid Shallow Breathing Index (RSBI = f/Vt) to predict weaning readiness from mechanical ventilation. Cut-off: < 105 breaths/min/L.

Calculate calories burned running from weight, distance and speed — uses MET values from the Compendium of Physical Activities.

Calculate the Serum-Ascites Albumin Gradient (SAAG) to differentiate portal hypertension from non-portal causes of ascites.

Calculate the SAPS II score and predicted ICU mortality from 15 clinical variables, based on the Le Gall 1993 scoring system.

Calculate a goalkeeper's save percentage (saves ÷ shots on goal × 100) and see how it rates against professional benchmarks.

Calculate the SCORAD index for atopic dermatitis (eczema) severity: extent, intensity, and subjective symptoms combined into a 0–103 score.

Estimate the starting ballast weight needed for neutral buoyancy when scuba diving — by body weight, suit, water type and tank.

Calculate the qSOFA score to screen for sepsis risk: respiratory rate, systolic BP, and mentation. Score ≥ 2 suggests high risk.

Calculate estimated serum osmolality from sodium, glucose and BUN using the standard clinical formula (2×Na + glucose/18 + BUN/2.8).

Calculate the Shock Index (heart rate ÷ systolic BP) to screen for haemodynamic instability. Normal SI is 0.5–0.7; values above 1.0 suggest significant shock.

Estimate your daily calorie intake for weight loss, maintenance or gain using the Harris-Benedict BMR formula and your activity level.

Calculate the right ski length for your height, ability level and skiing style — plus ski pole length.

Plan sleep timing for complete cycles using a configurable cycle length — find your ideal bedtime or wake time to avoid mid-cycle wake-ups.

Track your weekly sleep debt by comparing nightly actual sleep to your target — see your deficit, average, and estimated recovery time.

Calculate baseball slugging percentage (SLG = total bases ÷ at-bats), OBP and OPS. Weights singles, doubles, triples and home runs by base value.

Track your health recovery after quitting smoking: see which milestones you have reached, money saved, and how close you are to full cardiovascular recovery.

Estimate your Snapchat Snap Score from daily sending, receiving, and story activity — plus daily screen time for digital-wellness awareness.

Track how long you have been sober: convert days into weeks, months and years, see money saved, and visualise progress toward your next milestone.

Calculate the floor area needed to keep a group socially distanced, equivalent room dimensions, and the maximum safe capacity for any space.

Predict the change in serum sodium after any IV fluid using the Adrogue-Madias equation — enter Na, weight, fluid type and volume.

Correct serum sodium for high blood glucose using the Katz (1.6) and Hillier (2.4) formulas to find the true sodium level in hyperglycaemia.

Calculate the IV infusion rate (mL/hr) needed to raise serum sodium safely in hyponatraemia using the Adrogue-Madias equation.

Calculate the total sodium deficit (mEq) and volume of replacement fluid required to reach a target serum sodium in hyponatraemia.

Convert between table salt (NaCl) weight and sodium content in mg. See how teaspoons of salt compare to the WHO daily sodium limit of 2000 mg.

Calculate the SOFA score to assess organ dysfunction severity in ICU patients across 6 organ systems (0–24 scale).

Evaluate semen analysis results against WHO 2021 reference values: total count, concentration, motility and morphology.

Track your progress toward achieving front or straddle splits: enter your current hip clearance from the floor and weekly improvement to see how close you are and when you'll get there.

Calculate calories burned climbing stairs by body weight, floors climbed, and pace — based on MET values from the 2011 Compendium of Physical Activities.

Calculate the number of standard drinks in any alcoholic beverage from its volume and ABV. Supports Australian, UK and US definitions.

Convert step count to calories burned while walking — based on body weight, step length and distance.

Convert steps to kilometres, miles, metres and feet using your step length from a pedometer or fitness tracker.

Convert step count to miles, kilometres and calories burned using a height-based stride length estimate.

Estimate relative stillbirth risk from key population-level factors: maternal age, BMI, smoking, diabetes, and prior loss.

Screen for obstructive sleep apnea risk with the validated STOP-BANG questionnaire. Score 0–8 with low/intermediate/high risk categories.

Estimate walking or running stride length from height using De Vito regression constants, or calculate it from total distance and step count.

Calculate stroke volume from end-diastolic and end-systolic volumes (EDV − ESV) or from cardiac output divided by heart rate (CO ÷ HR).

Track your daily added sugar from drinks, snacks, and meals and compare it to the AHA 2023 recommended limit (25 g women, 36 g men, 25 g children).

Calculate calories burned swimming any stroke — freestyle, breaststroke, butterfly and more — using MET values from the Compendium of Physical Activities.

Calculate total swim time from distance, pace per 100 m and pool length — includes wall rest stops and split visualisation.

Model how stacking multiple imperfect COVID-19 protections (vaccine, mask, ventilation, distancing) reduces combined transmission risk.

Calculate the Testosterone-to-Estradiol (T:E2) ratio using T in ng/dL and E2 in pg/mL, with a reference range band for adult men.

Find your target heart rate training zone from age and resting heart rate using the Karvonen Heart Rate Reserve method or simple % of HRmax.

Calculate calories burned playing tennis — singles, doubles, or practice — based on body weight and session duration.

Calculate tidal volume for mechanical ventilation using ideal body weight (Devine formula) and minute ventilation.

Estimate time of death from body and ambient temperature using Newton's Law of Cooling. Educational model — not a forensic substitute.

Calculate the TIMI risk score for unstable angina and NSTEMI to estimate 14-day risk of major cardiac events.

Calculate the TIMI Risk Score for STEMI to estimate 30-day mortality in patients receiving fibrinolytic therapy (Morrow et al. JAMA 2000).

Assess fall risk in older adults using the Tinetti Performance-Oriented Mobility Assessment balance and gait score.

Calculate running pace per km and mile, speed, split times, and easy/tempo/interval training paces from any race distance and target time.

Estimate TIBC from transferrin and calculate transferrin saturation % to help assess iron status. Not a substitute for clinical diagnosis.

Calculate triathlon finish time, segment splits and calorie burn for sprint, Olympic, 70.3 and Ironman events from your swim, bike and run paces.

Calculate target heart rate zones for triathlon swim, bike and run disciplines using the Karvonen heart-rate-reserve method.

Calculate triathlon race split times and training zone paces (easy + tempo) for swimming, cycling and running from your target race paces.

Calculate the transtubular potassium gradient (TTKG) to assess renal potassium handling and differentiate renal from extrarenal causes of dyskalemia.

Calculate recommended total weight gain for a twin pregnancy using IOM 2009 guidelines by pre-pregnancy BMI, with progress tracking by gestational week.

Estimate the probability of conceiving twins based on maternal age, family history, prior twin pregnancies and fertility treatment.

Calculate the Urine Anion Gap (UAG = Na⁺ + K⁺ − Cl⁻) and interpret it to help differentiate renal from gastrointestinal causes of metabolic acidosis.

Calculate urine output rate in mL/kg/hr from collected volume, body weight, and time — with oliguria, normal, and polyuria classification.

Estimate whether a home urine pregnancy test would be positive based on days past ovulation, implantation timing, and test sensitivity.

Calculate herd immunity thresholds, required vaccination coverage, and effective reproduction number for any disease using R₀ and vaccine efficacy.

Calculate vaccine efficacy (VE), relative risk, absolute risk reduction and number needed to vaccinate from clinical trial or observational study data.

Calculate the herd immunity threshold (HIT) from R₀, the minimum vaccine coverage needed, and whether current vaccination + natural immunity is sufficient to stop an epidemic.

Estimate annual vaccine dose output from bioreactor volume, yield, batch duration, number of bioreactors, and fill-finish efficiency.

Estimate your place in Australia's 2021 COVID-19 vaccine priority queue based on age, healthcare role, and health conditions.

Estimate your place in Canada's 2021 COVID-19 vaccine priority queue based on age, healthcare role, long-term care status, and health conditions.

Estimate your place in England's 2021 COVID-19 JCVI vaccine priority queue based on age, clinical status, and healthcare role.

Estimate your place in India's 2021 COVID-19 vaccine priority queue based on age, healthcare worker status, and comorbidities.

Estimate your place in Malaysia's 2021 PICK COVID-19 vaccine priority queue based on age, frontline status, comorbidities, and essential worker role.

Estimate how long you would wait for a COVID-19 vaccine in the Netherlands based on your priority group, population and daily vaccination capacity.

Estimate your COVID-19 vaccine wait time in Northern Ireland based on your JCVI priority group, population and daily vaccination capacity.

Estimate your COVID-19 vaccine wait time in the Philippines based on your A/B priority group, population size and daily vaccination capacity.

Estimate your COVID-19 vaccine wait time in Scotland based on your JCVI priority group, population and daily vaccination capacity.

Estimate your COVID-19 vaccine wait time in South Africa based on your EVDS phase, population size and daily vaccination capacity.

Estimate your COVID-19 vaccine wait time in the UK based on your JCVI priority group, UK population and daily vaccination capacity.

Estimate when you would have received your COVID-19 vaccine in Wales based on your 2021 JCVI priority group and the daily rollout rate.

Calculate the Flamm-Geiger VBAC admission score (0–10) to estimate the likelihood of a successful vaginal birth after cesarean.

Calculate venous blood pH from HCO₃⁻ and PvCO₂ using Henderson-Hasselbalch and estimate arterial pH from venous values.

Model viral epidemic spread with the SIR compartmental model — compute R₀, peak infections and herd immunity threshold.

Estimate predicted vital capacity (FVC) by age, sex and height using ECSC 1993 reference equations; compare your measured result as % of predicted.

Convert vitamin A intake from IU to mcg RAE, combine retinol and beta-carotene sources, and compare with the RDA and upper safety limit.

Look up recommended daily vitamin intakes (RDAs) for vitamins A, C, D, E, K, B6, B12 and folate based on your age and sex.

Convert vitamin D between IU and mcg, add estimated sun synthesis, and compare total intake against the RDA (600–800 IU) and upper limit (4,000 IU).

Calculate VLDL cholesterol (Triglycerides ÷ 5) and Friedewald LDL from a standard lipid panel in mg/dL or mmol/L.

Estimate VO2 max (mL/kg/min) from the Cooper 12-min run, Rockport 1-mile walk test or resting heart rate method, with ACSM fitness category.

Estimate your VO₂ max from a Cooper 12-minute run test or a recent race time using the Jack Daniels formula.

Estimate venous thromboembolism (DVT/PE) risk in pregnancy and the postpartum period using RCOG guideline risk factors.

Calculate your waist-to-height ratio (WHtR) and see your cardiovascular risk zone — keep it under 0.5 for a healthy range.

Find the right bedtime (or wake-up time) given your target sleep duration and how long you take to fall asleep.

Calculate calories burned walking from body weight, duration and speed using MET values from the Compendium of Physical Activities.

Estimate daily energy and protein requirements for hospital patients using the Warsaw clinical nutrition method (25 kcal/kg × activity × stress factor).

Calculate your daily water deficit or surplus by comparing your actual fluid intake with your weight-, activity-, and climate-adjusted recommended intake.

Calculate the daily calories needed to gain weight, your TDEE, weekly gain rate, protein target, and how long it will take to reach your goal.

Calculate your daily calorie target for weight loss, TDEE, weekly loss rate, and how long it takes to reach your goal weight.

Calculate what percentage of your starting body weight you have lost, remaining weight to your goal, and progress towards it.

Estimate WW SmartPoints and PointsPlus from a food's nutrition label using publicly reverse-engineered formulas.

Track weight loss or gain week by week: enter your starting, current, and goal weight to see your average weekly rate and how many weeks remain.

Calculate the Wells clinical prediction score for pulmonary embolism risk: low (< 2), moderate (2–6), or high (> 6) with estimated PE probability.

Calculate a baseball pitcher's WHIP (Walks plus Hits per Inning Pitched). Enter walks, hits, and innings pitched to get WHIP and a performance rating.

Calculate your Wilks score to compare powerlifting totals across body weights using the original Wilks formula (pre-2019).

Calculate calories burned windsurfing, apparent wind speed and angle, estimated boat speed, and recommended sail size for the conditions.

Calculate winning percentage from wins, losses and ties using the standard formula (W + 0.5×T) / games × 100.

Use Winter's formula to find the expected PCO₂ in metabolic acidosis and determine whether respiratory compensation is appropriate.

Estimate calories burned during a World Cup football match — watching at home, cheering at the stadium, or playing on the pitch.