CLINICAL TOOLS, IN ONE PLACE
Clinical calculators
Find common scores, clinical decision rules, and bedside formulas. Review the intended population, enter confirmed values, and see the result with its source references.
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Showing 50 of 50 calculators and decision rules
ABCD² after suspected TIA
Historical early-stroke risk score after a clinician-assessed transient ischemic attack.
Open calculator HematologyAbsolute neutrophil count (ANC)
Calculate ANC from the WBC count and separately reported neutrophil and band percentages.
Open calculator Electrolytes and acid–baseAlbumin-adjusted calcium (conventional)
Show the conventional albumin correction while making its limitations explicit.
Open calculator Electrolytes and acid–baseAnion gap (without potassium)
Calculate the serum anion gap with the no-potassium convention.
Open calculator Body sizeBody mass index (BMI)
Adult weight relative to height, with standard adult BMI categories.
Open calculator Body sizeBody surface area (Mosteller)
Estimate body surface area from measured height and weight.
Open calculator Electrolytes and acid–baseCalculated serum osmolality
Estimate serum osmolality using sodium, glucose and blood urea nitrogen.
Open calculator Emergency & traumaCanadian C-Spine Rule
Stepwise cervical imaging rule with safe sequencing of neck rotation.
Open calculator Emergency & traumaCanadian CT Head Rule
High- and medium-risk criteria for CT after minor head injury.
Open calculator Emergency & traumaCanadian Syncope Risk Score
30-day serious-outcome risk stratification after a completed ED syncope assessment.
Open calculator Cardiovascular & clot riskCHA₂DS₂-VASc
Stroke risk factors in atrial fibrillation, with sex category as a risk modifier.
Open calculator CardiovascularCorrected QT interval (QTc)
Show Bazett and Fridericia heart-rate corrections from a measured QT and RR interval.
Open calculator HematologyCorrected reticulocytes and production index
Show corrected reticulocyte percentage and RPI using explicit reference and maturation inputs.
Open calculator Pulmonary & infectionCRB-65
Adult community-acquired pneumonia severity and mortality risk categories.
Open calculator Kidney functionCreatinine clearance (Cockcroft–Gault)
Historical adult estimate of creatinine clearance using an explicitly selected weight.
Open calculator Pulmonary & infectionCURB-65
Adult community-acquired pneumonia severity and mortality risk categories.
Open calculator Kidney functioneGFR (CKD-EPI 2021, race-free)
Adult creatinine-based, race-free estimated glomerular filtration rate.
Open calculator Kidney functionFractional excretion of sodium (FENa)
Calculate fractional sodium excretion from paired blood and urine samples.
Open calculator Kidney functionFractional excretion of urea (FEUrea)
Calculate fractional urea excretion with matched urine and blood urea-nitrogen measurements.
Open calculator Electrolytes and acid–baseFree-water deficit estimate
Estimate water deficit to a stated sodium reference using an explicitly entered body-water fraction.
Open calculator Mental healthGAD-2
Two-item anxiety screening tool.
Open calculator Mental healthGAD-7
Seven-item anxiety symptom severity screen.
Open calculator NeurologyGlasgow Coma Scale
Record eye, verbal, and best motor responses with the component notation.
Open calculator Cardiovascular & clot riskHAS-BLED
Identify bleeding-risk factors that warrant review in adults with atrial fibrillation.
Open calculator CardiovascularHEART score
Five-component ED chest-pain risk score.
Open calculator CardiovascularMean arterial pressure (estimated)
Estimate cycle-averaged arterial pressure from systolic and diastolic readings.
Open calculator Infection & respiratoryModified Centor / McIsaac
Age-adjusted GAS pharyngitis clinical score.
Open calculator Emergency & traumaNew Orleans head CT criteria
Seven CT criteria in adults with GCS 15 after minor head trauma.
Open calculator Pulmonary & infectionNEWS2
Royal College of Physicians National Early Warning Score 2 with both oxygen saturation scales.
Open calculator Emergency & traumaNEXUS cervical spine
Five clinical low-risk criteria after blunt cervical trauma.
Open calculator MusculoskeletalOttawa ankle & foot rules
Separate ankle and midfoot radiograph indications after acute injury.
Open calculator MusculoskeletalOttawa Knee Rule
Five criteria for radiographs following acute knee trauma.
Open calculator NeurologyOttawa subarachnoid hemorrhage rule
Identify need for SAH investigation in a defined acute-headache population.
Open calculator Emergency & traumaPECARN pediatric head injury
Age-specific head CT decision support after pediatric blunt head trauma.
Open calculator Kidney functionPediatric eGFR (bedside Schwartz 2009)
Historical bedside pediatric creatinine estimate from the CKiD cohort.
Open calculator FluidsPediatric maintenance fluids (Holliday–Segar)
Calculate the conventional daily weight-based maintenance estimate, with its exact hourly equivalent.
Open calculator Cardiovascular & clot riskPERC rule
Pulmonary embolism rule-out criteria for a clinician-selected very-low-risk adult.
Open calculator Mental healthPHQ-2
Two-item depression screening tool.
Open calculator Mental healthPHQ-9
Nine-item depression symptom screen with an item 9 safety alert.
Open calculator CardiovascularPREVENT-ASCVD
Race-free base PREVENT estimate of 10-year ASCVD risk; 30-year estimate for ages 30–59.
Open calculator Pulmonary & infectionqSOFA
Three bedside findings associated with worse outcomes in adults with suspected infection.
Open calculator PediatricsRDAI
Respiratory Distress Assessment Instrument: observed wheeze and retractions.
Open calculator Cardiovascular & clot riskShock index
Heart rate divided by systolic blood pressure.
Open calculator Cardiovascular & clot riskSimplified PESI (sPESI)
Six-item mortality-risk stratification after pulmonary embolism is diagnosed.
Open calculator Pulmonary & infectionSIRS criteria
Count the four original adult systemic inflammatory response criteria.
Open calculator Electrolytes and acid–baseSodium correction for hyperglycemia
Estimate glucose-adjusted sodium with an explicitly selected published coefficient.
Open calculator Cardiovascular & clot riskWells score for DVT
Two-level lower-extremity DVT clinical probability.
Open calculator Cardiovascular & clot riskWells score for pulmonary embolism
Two-level clinical pretest probability of pulmonary embolism.
Open calculator Electrolytes and acid–baseWinter's formula
Expected respiratory compensation range for an established metabolic acidosis.
Open calculator Cardiovascular & clot riskYEARS algorithm
Three clinical items with a protocol-specific D-dimer threshold for suspected PE.
Open calculatorA score is part of the assessment.
Use each tool only in its validated population. Results support clinical judgment and local workflows; they do not replace assessment or determine treatment on their own.