Sixty validated health calculators sit in this hub across twelve clinical domains: cardiovascular risk, metabolic and endocrine screening, kidney function, liver disease, emergency scoring, reproductive health, pediatrics, bone density, mental health, respiratory function, drug dosing, and general wellbeing. Some are patient-facing screens (BMI, blood pressure, depression questionnaires). Others are clinician-grade scoring systems (ASCVD, MELD, CHA2DS2-VASc, qSOFA). Every formula traces to peer-reviewed published work. Use these tools to bring a number to your next appointment, not to skip the appointment.

Why These Numbers Matter

Most clinical risk scores were designed for clinicians, then leaked into patient hands without translation. The ASCVD risk calculator outputs "your 10-year risk of heart attack or stroke is 7%," but it does not tell you what to do at 7%, or 12%, or 20%. The MELD score for liver disease ranks transplant priority but does not say where to start eating differently. This page exists to bridge that gap.

A representative example. The Pooled Cohort Equations behind the ASCVD calculator were validated against the ARIC, CHS, MESA, and Framingham Offspring cohorts (Goff et al., 2014, Circulation, vol. 129), over 130,000 patient-years of follow-up. The result is a number with real predictive power: a 10-year risk above 7.5% is the AHA/ACC threshold for statin discussion. But it is one input weighted against patient preference and side-effect tolerance. Numbers diagnose; they do not prescribe.

The sixty calculators in this hub each output a number with similar provenance. The job of the rest of this page is to tell you which to run when, and how to read what comes out.

Cardiovascular Risk: From Blood Pressure to 10-Year ASCVD

The largest cluster in this hub is cardiovascular, because cardiovascular disease remains the leading cause of death globally (WHO Global Health Estimates 2023). Eight calculators in the cardiovascular sub-section cover the staircase from a single home BP reading to formal 10-year risk estimation.

Start with the simplest measurement. Check a blood pressure reading against the AHA/ACC 2017 thresholds. Stage 1 hypertension is now ≥130/80, not ≥140/90, which moved millions of adults into a new risk band overnight. From the same set of inputs, mean arterial pressure (MAP) gauges perfusion across organs and is the more useful number in critical-care contexts.

Lipid risk needs more than total cholesterol. The total/HDL and LDL/HDL ratios separate "good" from "bad" cholesterol burden, with a TC/HDL ratio above 4.5 flagging elevated risk.

Composite 10-year scores synthesise multiple inputs. The ASCVD risk calculator using the Pooled Cohort Equations is the current AHA/ACC standard for primary-prevention statin decisions. The Framingham Risk Score is the older lineage and remains widely used for context and international cohorts.

Rhythm and rate sit alongside risk. The CHA2DS2-VASc score for stroke risk in atrial fibrillation determines anticoagulation eligibility. A score of 2 or more in a man (or 1 or more in a woman) typically triggers a DOAC discussion. The QTc interval calculator for ECG-based arrhythmia screening handles four correction formulas (Bazett, Fridericia, Framingham, Hodges) for QT-prolonging drugs. And the exercise-prescription heart-rate target applies the Karvonen formula for cardiac rehab and routine exercise prescription.

Metabolic and Endocrine Screening

The eight calculators in the metabolic sub-section screen for the diseases that quietly run on insulin resistance, glucose dysregulation, and thyroid imbalance.

Glucose screening covers three angles. The FINDRISC type-2 diabetes risk score is a validated 0-26 score where ≥15 flags high risk and triggers an OGTT. For patients already monitoring blood sugar, the HbA1c-to-average-glucose conversion (eAG) translates lab numbers into the day-to-day reading from a glucometer. And convert HbA1c to a personalised glucose target range when titrating to an ADA-recommended ≤7% goal.

Insulin resistance is the upstream story. The HOMA-IR score from fasting insulin and glucose uses the Matthews 1985 formula; ≥2.5 is a common cut-off for insulin resistance, though normal ranges vary by lab and ethnicity.

Body composition and metabolic age complete the screen. Run a WHO BMI category check for adults when a single fitness BMI is not enough; obesity class affects medication dosing and surgical-risk scores. The metabolic-age estimate compares your BMR against population averages, useful as a motivation framing rather than a clinical diagnosis.

Thyroid and acid-base round out the cluster. The levothyroxine starting-dose tool outputs μg/day from body weight and indication; the standard 1.6 μg/kg dose is reasonable for newly-diagnosed primary hypothyroidism. The anion gap calculator for acid-base evaluation flags metabolic acidosis (gap >12 mEq/L) with optional potassium and albumin corrections.

Kidney and Electrolyte Function

The renal and electrolyte sub-section holds six tools for kidney function, fluid balance, and electrolyte correction.

Filtration rate is the headline measurement. The eGFR calculator using the 2021 CKD-EPI equation (race-free) replaces the older MDRD and the race-corrected CKD-EPI 2009; it is the current KDIGO standard for CKD staging. Below 60 ml/min/1.73 m² for three months is CKD stage 3 or worse. The Cockcroft-Gault creatinine clearance calculator remains the formula most drug-dosing labels reference, so it is the right one for pharmacology decisions even where eGFR is preferred for staging.

Fluid balance covers three calcs. The Watson formula estimates total body water (roughly 60% of body weight for men, 50% for women) and supplies the volume of distribution for sodium correction math. The corrected-sodium-for-hyperglycemia formula (Katz 1973) prevents the classic overdiagnosis of hyponatremia in DKA and HHS. The Holliday-Segar 4-2-1 maintenance IV fluid rate outputs hourly drip rate by body weight, the bedside standard since 1957.

Calcium fills the last slot, sitting between nutrition and bone health. The daily calcium intake assessment against age-band recommendations flags adults below the 1,000 to 1,200 mg/day target, particularly relevant for postmenopausal women on osteoporosis risk.

Liver and GI Scoring

Four calculators in the liver sub-section score chronic liver disease severity and screen for fibrosis without biopsy.

Two prognostic scores anchor advanced liver disease. The MELD score (MELD-Na since 2016) ranks transplant priority using bilirubin, INR, creatinine, and sodium; UNOS uses it to allocate livers in the US. The Child-Pugh score classifies cirrhosis severity from A to C using bilirubin, albumin, INR, ascites, and encephalopathy; it remains the standard for surgical risk in cirrhotic patients.

Fibrosis screening replaces a lot of biopsies. The FIB-4 index from age, AST, ALT, and platelet count is the first-line non-invasive fibrosis test in viral hepatitis and NAFLD; below 1.3 rules out advanced fibrosis in most adults, above 2.67 suggests F3 or F4. For confirmed non-alcoholic fatty liver disease, the NAFLD Fibrosis Score adds BMI, diabetes status, and AST/ALT ratio and stratifies the same disease cohort with comparable accuracy.

Emergency and Critical Care Scoring

The critical-care sub-section contains six bedside scoring tools used in emergency departments and ICUs worldwide. These are clinician-grade, but informed patients and caregivers can use the same scores to understand a hospitalisation.

Sepsis screening sits at the front door. The qSOFA score (respiratory rate ≥22, altered mental status, SBP ≤100) flags suspected-infection patients at risk of poor outcomes; ≥2 of 3 criteria triggers escalation. For respiratory infections specifically, CURB-65 stratifies community-acquired pneumonia severity and guides outpatient-vs-inpatient disposition.

Hemodynamics and trauma share two tools. The shock index (heart rate divided by systolic blood pressure) flags occult hemorrhage when above 1.0, well before traditional vital signs become abnormal. The Wells DVT score stratifies deep vein thrombosis probability before D-dimer testing, with ≥3 points triggering imaging.

ICU prognosis and neurology each get a tool. The APACHE II score from 12 physiologic variables estimates ICU mortality risk; a score of 25 corresponds to roughly 55% predicted mortality. And the Glasgow Coma Scale (eye, verbal, motor) is the universal language of consciousness assessment, from prehospital trauma to ICU sedation holds.

Reproductive and Women's Health

The women's health sub-section covers five tools spanning conception, pregnancy, labour, and the menopause transition.

For conception and early pregnancy, the ovulation calculator estimates fertile windows and ovulation dates across multiple cycles. It is most accurate for users with cycles of 26 to 32 days; irregular cycles need ovulation strips or basal-body-temperature tracking as adjuncts. Once pregnant, the due-date calculator using Naegele's Rule outputs gestational age and estimated delivery date from the last menstrual period.

During pregnancy, the weight-gain tracker against the IOM 2009 recommended ranges by BMI category prevents both under-gaining (associated with low birth weight) and over-gaining (associated with gestational diabetes and post-partum retention). Underweight women target 12.5 to 18 kg total gain; obese women target 5 to 9 kg.

At the end of pregnancy, the Bishop score assesses cervical readiness for labour induction from dilation, effacement, station, consistency, and position. A score of 8 or above predicts induction success comparable to spontaneous labour.

Past reproductive years, the menopause symptom severity score (modified Kupperman index) tracks hot flashes, sleep disturbance, mood symptoms, and joint complaints across the perimenopausal transition; it helps frame HRT and lifestyle conversations with a clinician.

Pediatric Tools

The pediatric sub-section holds four tools that handle the medical math specific to infants and children.

The first contact is at birth. The APGAR score (appearance, pulse, grimace, activity, respiration) is the universal newborn assessment at 1 and 5 minutes post-delivery; a score below 7 at 5 minutes flags need for further evaluation. The 0 to 10 scale has not changed since Virginia Apgar's 1952 paper.

After the newborn window, growth tracking becomes the long arc. The WHO/CDC growth percentile calculator for weight and height by age and sex plots a child's measurements against population standards; a sustained drop across two major percentile bands warrants pediatrician review. The pediatric BMI percentile calculator uses CDC growth charts (different from adult BMI math) for children aged 2 to 19; ≥85th percentile is overweight, ≥95th is obese.

Medication dosing closes out the section. Most pediatric drugs dose by body weight in mg/kg, and the calculator outputs single dose, daily dose, and liquid medicine volume from a concentration. It is meant for caregiver double-checking against a prescription, not as a substitute for one.

Bone Density and Body Surface Math

Four tools in the bone and musculoskeletal sub-section handle fracture risk, surface-area dosing, and vitamin D.

Fracture risk screening drives osteoporosis treatment decisions. The FRAX 10-year fracture probability tool from age, sex, weight, height, and clinical risk factors is the WHO-supported standard; treatment thresholds vary by country, but a 10-year major osteoporotic fracture risk above 20% or a hip fracture risk above 3% commonly triggers bisphosphonate discussion. The ORAI screening score identifies postmenopausal women who should get a DXA scan, using just age, weight, and current oestrogen use.

Drug dosing for chemotherapy and burns uses body surface area, not weight. The BSA calculator across DuBois, Mosteller, Haycock, and Gehan-George formulas lets you compare formulas; the spread is typically under 5% for adults but widens for the very small or very large.

Vitamin D anchors the cluster's nutritional side. The vitamin D status assessment from a serum 25(OH)D level plus supplementation dose calculator flags deficiency (under 20 ng/mL or 50 nmol/L) and outputs an IU/day target by current level, body weight, and goal range.

Mental Health and Behavioural Screening

The mental health sub-section holds five validated questionnaires that are the same instruments used in primary care.

Depression and anxiety screening run on two well-validated tools. The PHQ-9 nine-item depression screener scores 0 to 27, with 10 or above indicating moderate-or-worse depression and triggering a clinical conversation; sensitivity is 88% and specificity 88% at that cut-off (Kroenke et al., 2001). The GAD-7 seven-item generalised anxiety screener parallels PHQ-9 in design and scoring band logic; 10 or above flags moderate-or-worse anxiety.

Stress and sleep are the two adjacent state-of-mind measurements. The PSS-10 perceived stress score is a 10-item Cohen-Williamson questionnaire with established normative data by age and sex. The Pittsburgh Sleep Quality Index summarises seven components into a global score where ≤5 is good sleep, 6 to 10 is poor, and above 10 is very poor.

Substance use screening rounds out the cluster. The AUDIT 10-item alcohol-use screener from the WHO is the most internationally validated alcohol screening tool, with scores 8 to 14 indicating hazardous drinking and 15 or above suggesting dependence; it is routinely administered in primary care across high-income health systems.

Every one of these screening tools complements rather than replaces a clinician conversation. A positive screen is the start of a diagnostic process, not the end of one.

Respiratory Function and Oxygenation

The respiratory sub-section holds three calculators for lung function and oxygenation efficiency.

Asthma management uses peak flow at home. The peak expiratory flow rate calculator (Nunn and Gregg) outputs predicted PEF from age, sex, and height, and slots a measured value into the green/yellow/red zones of a standard asthma action plan; below 50% of predicted is the red zone signalling urgent rescue therapy.

Oxygenation efficiency uses two calculations. The A-a gradient (alveolar-arterial oxygen difference) flags ventilation-perfusion mismatch and shunt physiology; a gradient over (age/4 + 4) is broadly abnormal. The oxygenation index from FiO2, mean airway pressure, and PaO2 is the standard severity measure in pediatric and adult respiratory failure; OI above 25 in pediatric ARDS triggers consideration of ECMO referral.

Pharmacology: Equivalents, Conversions, Anticoagulation

The dosing sub-section holds three high-stakes drug-math tools used daily in clinical practice.

Opioid prescribing is increasingly driven by morphine equivalents. The MME calculator using CDC 2022 conversion factors sums total daily MME across oxycodone, hydrocodone, fentanyl, methadone, tramadol, codeine, and hydromorphone. The CDC flags 50 MME/day for caution and 90 MME/day as a hard threshold requiring justification.

Corticosteroid swaps happen routinely for cost, allergy, or duration reasons. The steroid-equivalency calculator (Meikle and Tyler 1977) handles prednisone, methylprednisolone, dexamethasone, hydrocortisone, and betamethasone; the relative potencies have not meaningfully changed in 50 years.

Warfarin remains the trickiest commonly-prescribed medication. The warfarin dose calculator estimates an initial dose or adjusts an existing one based on current INR, informed by the IWPC algorithm. It does not replace formal pharmacist-led dosing services but offers a reasonable bedside reference for an INR that has drifted out of range.

General Wellbeing: Aging, Activity, Composition

The general wellbeing sub-section holds four tools that take a broader view of health than any single organ system.

Two longevity-adjacent estimators frame the long arc. The biological-age calculator from blood pressure, fitness, body composition, and lifestyle markers outputs an age band that may differ substantially from chronological age; treat it as a motivational framing, not a clinical diagnosis. The life-expectancy estimator from lifestyle factors and health history integrates smoking status, BMI, exercise, alcohol, and family history into a projected outlook.

Body composition gets a clinical-style estimator. The body fat mass calculator using the Deurenberg and CUN-BAE formulas provides an alternative to the Navy-method approach in the fitness hub, validated in larger and more diverse cohorts.

Walking distance closes the section. The step-to-distance converter using a height-adjusted stride length is the simplest health-tracking tool here. 8,000 to 10,000 daily steps is associated with substantially lower all-cause mortality (Paluch et al., 2022, JAMA Network Open), with most of the benefit captured by the first 7,500 steps.

Finding Your First Calculator: A Triage Flow

The right starting tool depends on whether you arrived here as a patient, a caregiver, or a clinician. Run through these branches in order.

You have a fresh diagnosis or test result. Match the system. New high cholesterol or hypertension reading: run the ASCVD 10-year risk score to put the number in absolute-risk terms. Prediabetes flagged on bloodwork: the FINDRISC type-2 diabetes risk score. New osteopenia or osteoporosis on DXA: the FRAX 10-year fracture risk reframes the bone-density number into a treatment-relevant probability. Hepatitis or fatty liver mentioned: the FIB-4 fibrosis screen tells you whether deeper investigation is needed.

You are managing a chronic condition. Pick the monitoring number that matches what you adjust. On a statin and tracking lipids, use the cholesterol ratio every 6 months. Diabetic and titrating insulin, convert HbA1c to estimated average glucose so you can compare lab numbers to home glucometer readings. On warfarin, check the dose-adjustment tool whenever an INR drifts. Levothyroxine for hypothyroidism, the thyroid-dose calculator outputs the standard 1.6 μg/kg starting point if your TSH has run wild.

You are screening yourself or a family member. Start with the validated questionnaires. Mood feels off: run the PHQ-9. Worrying excessively: the GAD-7. Sleep keeps degrading: the PSQI. Drinking more than feels right: the AUDIT. None of these diagnose anything, but a score in the moderate-or-worse band is a strong nudge to book an appointment.

You are a clinician at the bedside. Pick the score that drives your next disposition decision. Suspected sepsis: qSOFA. Pneumonia severity for admit-vs-discharge: CURB-65. Possible DVT before D-dimer: Wells. AFib decision on anticoagulation: CHA2DS2-VASc. Liver failure for transplant priority: MELD-Na.

You are pregnant or planning pregnancy. Start with the due-date and gestational-age tool, then track weight gain monthly against the IOM ranges. Trying to conceive: the ovulation calculator estimates fertile windows. None of these replace prenatal care; they bring structure to the appointments.

Two Journeys, Five Calculators Each

Mateo, 58, New Hypertension and Prediabetes Diagnosis

Mateo is 175 cm, 92 kg, smokes a half-pack daily, total cholesterol 220 mg/dL with HDL 38 mg/dL, fasting glucose 108 mg/dL, BP 142/88. His GP flagged "let's talk about a statin and metformin at the follow-up."

Blood pressure risk band: 142/88 puts him at stage 2 hypertension per AHA/ACC 2017. The reading alone is not the news; the next step is integrating it.
ASCVD 10-year risk using age, sex, race, blood pressure, cholesterol, smoking, and diabetes status: 24%. Above the 20% high-risk threshold. Statin discussion is firmly indicated by guideline.
FINDRISC for type-2 diabetes risk: waist 105 cm, BMI 30.0, no daily 30-minute activity, family history positive. Score lands at 17, in the high-risk band, prompting an OGTT.
Cholesterol ratio: TC/HDL = 5.8, above the 4.5 risk threshold; LDL is also above the 100 mg/dL goal for primary-prevention statin candidates.
Body fat mass: 32%, consistent with the visceral-fat picture suggested by waist circumference and confirming the obesity contribution to his overall risk.

Honest critique: Mateo's plan worked on the medical side (statin started, metformin held pending OGTT) but the lifestyle side stalled. He left without a weight-loss anchor or a step-count goal. The step-to-distance converter in the fitness hub plus a structured calorie deficit would have given his lifestyle changes the same numeric framing his risk scores got.

Aisha, 34, Postpartum 4 Months

Aisha is 4 months postpartum after an uncomplicated delivery, breastfeeding, sleeping 4 hours in her longest stretch. She wants to know whether what she is feeling is normal new-parent territory or something more.

PHQ-9: Score of 14. Moderate depression. This is not normal-new-parent territory; the validated cut-off for treatment discussion is 10.
GAD-7: Score of 11. Moderate anxiety. Often comorbid with postpartum depression; a clinician will want to know both numbers.
PSQI: Global score of 14, "very poor" sleep. Expected given a 4-month-old breastfeeding pattern, but the number documents severity for the GP visit.
Pregnancy weight gain (looking back): She gained 14 kg during pregnancy (in the IOM range for her pre-pregnancy BMI) and is still 6 kg above pre-pregnancy weight. Normal trajectory for breastfeeding; not a reason to add calorie restriction now.
AUDIT: Score of 2. No alcohol-use concern.

Honest critique: Aisha brought all five scores to her GP and got an SSRI prescription and a postpartum mental-health referral within two weeks. The PHQ-9 and GAD-7 numbers anchored the visit far better than "I feel low and on edge" would have. The PSQI was the piece her GP might otherwise have minimised as "you have a baby, of course you are not sleeping."

Common Pitfalls When Stacking Health Calculators

Treating a screening score as a diagnosis. A PHQ-9 of 14 does not equal "major depressive disorder." It equals "high enough probability that a clinical interview is warranted." Same for the AUDIT score for hazardous drinking, the PSS-10 for stress, and the GAD-7 for anxiety. Screening tools are designed to be sensitive (catch most cases) rather than specific (rule out false positives), so positive screens always need clinical follow-through.

Using eGFR for drug dosing. One of the most common mix-ups. eGFR (CKD-EPI) is for CKD staging; drug labels overwhelmingly cite Cockcroft-Gault creatinine clearance for dose adjustment. Always run the Cockcroft-Gault formula when checking a renal-adjusted dose, particularly for direct oral anticoagulants and aminoglycosides where the two formulas can disagree by 10 to 20 ml/min in lean elderly patients.

Stacking risk scores without checking input overlap. ASCVD and Framingham use overlapping but non-identical inputs and validation cohorts. Running both gives a useful sense of model robustness, but only if the underlying inputs are the same. If the cholesterol numbers were from different blood draws, the scores are not directly comparable.

Re-using the wrong BMI formula for children. Adult BMI categories do not apply below age 18. The pediatric BMI percentile calculator using CDC growth charts handles this correctly; a "BMI of 22" in a 10-year-old is not equivalent to the same number in an adult. The same trap exists for adult BMI applied to athletes (use the fitness body-fat tools instead) and to pregnant women.

Calculating opioid MMEs incorrectly across formulations. A 25 μg/hr fentanyl patch is roughly 90 MME/day; a 10 mg oxycodone tablet is 15 MME. The conversion factors are not symmetric, and switching from one opioid to another at the same MME is risky because of incomplete cross-tolerance. The MME calculator outputs the total; the prescriber's reduction by 25 to 50% when switching is on the prescriber, not the math.

Ignoring the time horizon embedded in a risk score. ASCVD outputs a 10-year risk. FRAX outputs a 10-year risk. CHA2DS2-VASc outputs an annual stroke-rate range. These are not interchangeable. A 7% 10-year ASCVD risk is not "low" if the patient is 45 years old; lifetime risk projects much higher and the treatment threshold is therefore lower. Always read the time horizon before interpreting the percentage.

What This Category Doesn't Cover

The calculators here are diagnostic, prognostic, screening, and dosing tools. They do not handle training prescription, body-composition optimisation for athletes, or lifestyle planning around macros and recovery. If you are managing a chronic condition through exercise, want to plan a calorie deficit, build training-stress numbers for sport, or convert running pace and heart-rate zones into a weekly plan, those tools live in the fitness calculators pillar. The most important single cross-link in the cluster goes there.

Methodology and Sources

Every risk score in this hub links back to the original validation paper. The Pooled Cohort Equations (Goff et al., 2014, Circulation) anchor ASCVD; the Framingham Heart Study cohort anchors the original lineage. FRAX traces to the WHO Collaborating Centre at Sheffield (2008). MELD comes from Kamath et al. (2001, Hepatology) with the 2016 MELD-Na update. CHA2DS2-VASc is from Lip et al. (2010, Chest). PHQ-9 and GAD-7 come from Kroenke and Spitzer's primary-care validation work. APGAR remains Virginia Apgar's 1952 paper. Cockcroft-Gault (1976, Nephron) and CKD-EPI 2021 (Inker et al., 2021, NEJM) anchor renal function. AUDIT comes from the WHO's 1989 collaborative study.

These calculators are informational. They do not diagnose, treat, or prescribe. Clinical judgment overrides any number, particularly for high-stakes decisions (anticoagulation, transplant priority, ICU disposition). The point of bringing one of these numbers to an appointment is to make the conversation more specific, not to replace it.

Next Step

The fastest way to test whether this hub helps is to bring one number to your next appointment. If a recent test result has been worrying you, the matched risk score will reframe it as a probability rather than a binary good or bad. If you have no specific concern but are over 40, a Framingham risk score check gives a useful baseline cardiovascular probability. If your worry is mood, sleep, or anxiety, run the corresponding questionnaire today; clinicians strongly prefer to see a documented score than a vague "I have not been myself."

About health calculators.

Which health calculator should I run first?

Match the calculator to the question you arrived with. If you have a recent abnormal lab or vital, use the risk-scoring tool that integrates it (ASCVD for cholesterol/BP, FINDRISC for fasting glucose, FRAX for low DXA). If you are screening yourself, start with the validated questionnaires (PHQ-9, GAD-7, PSQI, AUDIT).

How accurate are clinical risk scores like ASCVD and FRAX?

ASCVD (Pooled Cohort Equations) has a C-statistic of around 0.74 in white populations, lower in some minority groups; it tends to over-predict by 10 to 30% in low-risk patients. FRAX validates well in the populations its country-specific models were built for but should not be used outside that scope. All risk scores bracket probability rather than predict outcome.

Should I use eGFR or creatinine clearance for drug dosing?

Use Cockcroft-Gault creatinine clearance for drug-dose adjustment. Drug labels and prescribing references almost universally cite CrCl, not eGFR. eGFR (CKD-EPI 2021) is the right number for staging chronic kidney disease. The two formulas can disagree by 10 to 20 ml/min in elderly or lean patients, with clinical consequences for narrow-window drugs.

Are these calculators a substitute for a clinician?

No. Risk scores generate inputs to a clinical conversation, not outputs of one. The ASCVD calculator tells you a 10-year risk percentage; the clinician decides whether and how to act on it given your full history, preferences, and side-effect tolerance. Use these tools to walk into appointments better prepared, not to skip them.

What does a high PHQ-9 score actually mean?

A PHQ-9 of 10 to 14 is moderate depression, 15 to 19 is moderately severe, 20 or above is severe. Each band has different treatment implications: 10 or above generally warrants clinical attention, 15 or above typically supports pharmacotherapy or formal psychotherapy. The score is not a diagnosis but it has good test characteristics (sensitivity 88%, specificity 88% at the 10 cut-off).

How often should I recheck my blood pressure risk?

For confirmed hypertension on medication, BP checks belong in the routine clinic visit schedule (every 3 to 6 months). For risk reassessment without a diagnosis, every 1 to 2 years is reasonable in adults aged 40 and up; sooner if a lifestyle factor changed (significant weight loss, smoking cessation). Update your ASCVD 10-year risk number when lipids are next drawn.

Can I use the pediatric calculators for my teen?

The pediatric BMI calculator covers ages 2 to 19 (CDC growth charts). The growth percentile calculator covers 0 to 19. The weight-based child dosing calculator is intended for infants through adolescents on weight-based prescriptions; once a teen hits adult-dosing weight (typically 50 kg), use adult drug references. The APGAR score is newborn-only.

Are the women's health calculators valid for irregular cycles?

The ovulation and due-date calculators assume reasonably regular cycles in the 26-to-32-day range and ovulation around day 14. Users with PCOS, perimenopausal cycle irregularity, or post-pill amenorrhea will find these less accurate; pair them with ovulation-prediction strips or basal-body-temperature charting for confirmation.

What is the difference between ASCVD and Framingham?

ASCVD uses the Pooled Cohort Equations validated in 2013 by the AHA/ACC on a multi-ethnic cohort. Framingham is the older lineage (1998 version most common) derived from a single, mostly-white Massachusetts cohort. Where both apply, ASCVD is the current US guideline standard. Framingham remains in international use and gives a useful sanity check.

Why does my home BP reading disagree with the clinic's?

Two effects. White-coat hypertension can add 5 to 10 mmHg in clinic; masked hypertension does the opposite. Cuff size, arm position, time of day, recent caffeine, and a 5-minute rested baseline all matter. Home readings averaged over 7 days (twice daily, both arms) generally beat single-clinic readings for cardiovascular-risk decisions, per 2017 AHA/ACC home-BP guidance.

How do I interpret a CHA2DS2-VASc of 2?

In atrial fibrillation, a score of 2 indicates an annual stroke risk of roughly 2.2% without anticoagulation, dropping below 1% on a DOAC or warfarin. Most guidelines recommend anticoagulation for men with a score of 2 or above and women with a score of 3 or above. The decision is not automatic; bleeding risk, patient preference, and bleeding history all factor in.

When should I redo a FRAX calculation?

Repeat FRAX every 1 to 2 years in untreated high-risk patients, or after any new fragility fracture, significant weight loss, glucocorticoid initiation, or new diagnosis of one of the FRAX risk factors. Treatment effect tracking is done via repeat DXA at 1-to-2-year intervals rather than serial FRAX, since the calculator inputs change slowly.

Health calculators

Explore all 60 health calculators across 12 sub-categories. Every formula links back to its source.

60 calculators12 sub-categoriesFree · instant · private

Cardiovascular & Heart

8 calculators in cardiovascular & heart.

CHA2

CHA2DS2-VASc Calculator

Calculate your CHA2DS2-VASc score to assess stroke risk in atrial fibrillation.

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HRT

Heart Rate Target Calculator

Calculate your target heart rate zone using the Karvonen formula for exercise prescription.

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BPR

Blood Pressure Risk Calculator

Assess your blood pressure reading against AHA/ACC 2017 guidelines.

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Cholesterol Ratio Calculator

Calculate key cholesterol ratios to assess cardiovascular risk.

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ASCVD Risk Calculator

Estimate your 10-year risk of atherosclerotic cardiovascular disease using the Pooled Cohort Equations.

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Framingham Risk Calculator

Calculate your 10-year coronary heart disease risk using the Framingham Risk Score.

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QTC

QTc Calculator

Calculate the corrected QT interval using Bazett, Fridericia, Framingham, and Hodges formulas.

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MAP

Mean Arterial Pressure Calculator

Calculate mean arterial pressure from systolic and diastolic blood pressure.

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Metabolic & Endocrine

8 calculators in metabolic & endocrine.

HOMA

HOMA-IR Calculator

Calculate insulin resistance using the Homeostatic Model Assessment (HOMA-IR).

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Metabolic Age Calculator

Estimate your metabolic age based on BMR compared to population averages.

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Glucose Target Calculator

Convert HbA1c to estimated average glucose (eAG) for diabetes management.

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BCC

BMI Category Checker

Determine your detailed WHO BMI category including obesity class and health risk.

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Diabetes Risk Calculator

Assess your type 2 diabetes risk using the Finnish FINDRISC score.

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HbA1c Converter

Convert HbA1c between NGSP (%), IFCC (mmol/mol), and estimated average glucose.

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Thyroid Dose Calculator

Calculate levothyroxine dosing based on body weight and clinical indication.

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Anion Gap Calculator

Calculate serum anion gap for acid-base evaluation, with optional potassium and albumin correction.

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Renal & Electrolyte

6 calculators in renal & electrolyte.

EGFR

eGFR Calculator

Estimate glomerular filtration rate using the CKD-EPI 2021 equation (race-free).

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Calcium Intake Calculator

Calculate your recommended daily calcium intake and assess your current status.

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Body Water Calculator

Estimate total body water using the Watson formula.

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Creatinine Clearance Calculator

Estimate creatinine clearance using the Cockcroft-Gault equation or calculate directly from urine measurements.

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Sodium Correction Calculator

Calculate corrected sodium for hyperglycemia using the Katz formula.

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IFR

IV Fluid Rate Calculator

Calculate maintenance IV fluid rate using the Holliday-Segar 4-2-1 rule.

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Liver & GI

4 calculators in liver & gi.

MELD Score Calculator

Calculate the Model for End-Stage Liver Disease (MELD) score with sodium adjustment.

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CHIL

Child-Pugh Calculator

Calculate the Child-Pugh score to assess the prognosis of chronic liver disease.

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FIB-

FIB-4 Calculator

Calculate the FIB-4 index to estimate liver fibrosis without biopsy.

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NAFLD Fibrosis Calculator

Calculate the NAFLD Fibrosis Score to identify advanced fibrosis in NAFLD patients.

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Critical Care & Emergency

6 calculators in critical care & emergency.

QSOF

qSOFA Calculator

Calculate the quick SOFA score for rapid bedside sepsis screening.

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CURB

CURB-65 Calculator

Calculate the CURB-65 score to assess pneumonia severity and guide disposition.

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Shock Index Calculator

Calculate the shock index (heart rate / systolic BP) to assess hemodynamic stability.

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APACHE II Calculator

Calculate the APACHE II score to estimate ICU mortality risk using all 12 acute physiologic variables.

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GCS

Glasgow Coma Scale Calculator

Calculate the Glasgow Coma Scale score for neurological assessment.

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Wells DVT Calculator

Calculate the Wells score to estimate probability of deep vein thrombosis.

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Women's & Reproductive Health

5 calculators in women's & reproductive health.

PDD

Pregnancy Due Date Calculator

Calculate your estimated due date and gestational age using Naegele's Rule.

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Bishop Score Calculator

Calculate the Bishop score to assess cervical readiness for labor induction.

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MSS

Menopause Symptom Score Calculator

Rate menopause transition symptoms to track severity and guide treatment decisions.

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OVUL

Ovulation Calculator

Estimate your ovulation dates, fertile windows, and due dates across multiple cycles.

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PWG

Pregnancy Weight Gain Calculator

Track pregnancy weight gain against IOM 2009 recommended ranges by BMI category.

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Pediatric

4 calculators in pediatric.

CGP

Child Growth Percentile Calculator

Estimate your child's growth percentiles for weight and height using WHO standards.

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APGAR Score Calculator

Calculate the APGAR score for rapid neonatal assessment at birth.

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Child Dosage Calculator

Calculate weight-based medication dosing for pediatric patients.

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Pediatric BMI Calculator

Calculate BMI percentile for children and teens using CDC growth charts.

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Bone & Musculoskeletal

4 calculators in bone & musculoskeletal.

FFR

FRAX Fracture Risk Calculator

Estimate 10-year fracture probability using the simplified FRAX assessment.

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BSA

Body Surface Area Calculator

Calculate body surface area using DuBois, Fujimoto, Gehan & George, Haycock and Mosteller formulas.

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Vitamin D Calculator

Assess vitamin D status and calculate supplementation dosing.

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OR(

Osteoporosis Risk (ORAI) Calculator

Calculate the Osteoporosis Risk Assessment Instrument score for bone density testing.

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Mental Health & Wellbeing

5 calculators in mental health & wellbeing.

SS(

Stress Score Calculator (PSS-10)

Measure perceived stress using the validated PSS-10 questionnaire.

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SQI(

Sleep Quality Index (PSQI)

Assess sleep quality using the Pittsburgh Sleep Quality Index component scoring.

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PDS

PHQ-9 Depression Screening

Screen for depression severity using the validated PHQ-9 questionnaire.

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GAS

GAD-7 Anxiety Screening

Screen for generalized anxiety disorder severity using the validated GAD-7 questionnaire.

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AAS

AUDIT Alcohol Screening

Screen for hazardous alcohol use with the WHO AUDIT questionnaire.

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Respiratory

3 calculators in respiratory.

Oxygenation Index Calculator

Calculate the oxygenation index to assess severity of hypoxemic respiratory failure.

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PEF

Peak Expiratory Flow Calculator

Calculate predicted peak expiratory flow and assess asthma control zones.

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A-a Gradient Calculator

Calculate the alveolar-arterial oxygen gradient to evaluate oxygenation efficiency.

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Dosing & Pharmacology

3 calculators in dosing & pharmacology.

Opioid MME Calculator

Convert opioid doses to morphine milligram equivalents per CDC guidelines.

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Steroid Conversion Calculator

Convert between corticosteroid doses using standard equivalency tables.

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Warfarin Dose Calculator

Estimate initial warfarin dose or adjust an existing dose based on current INR.

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General Health and Wellbeing

4 calculators in general health and wellbeing.

BFM

Body Fat Mass Calculator

Estimate body fat percentage and mass using the Deurenberg and CUN-BAE formulas.

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STDC

Step to Distance Converter

Convert your daily step count to distance in kilometers and miles.

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Biological Age Calculator

Estimate your biological age based on key health and lifestyle biomarkers.

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Life Expectancy Calculator

Estimate life expectancy based on lifestyle factors and health history.

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