All calculators

Calculate the alveolar–arterial oxygen gradient from ABG values and compare with age-expected normals.

Compute absolute neutrophil count from WBC and neutrophil/band percentages or fractions.

Estimate blood volume by age group and calculate allowable blood loss before a target hematocrit.

Score clinical likelihood of acute appendicitis using the Alvarado (MANTRELS) criteria.

Calculate serum anion gap with optional albumin correction for acid-base workups.

Compute the 1- and 5-minute Apgar score from appearance, pulse, grimace, activity, and respiration.

Estimate bicarbonate deficit from weight, current HCO₃, and target.

Assess cervical favorability for labor induction using the Bishop score.

Calculate body mass index from metric or imperial measurements with WHO category labels.

Calculate body surface area with Mosteller, DuBois & DuBois, Haycock, or Gehan & George formulas. Compare all methods side by side.

Estimate percent TBSA with Rule of Nines and calculate Parkland crystalloid resuscitation volumes.

Estimate group A strep pharyngitis probability with the modified Centor (McIsaac) score.

Estimate stroke risk in nonvalvular atrial fibrillation to guide anticoagulation decisions.

Classify cirrhosis severity (A/B/C) using bilirubin, albumin, INR, ascites, and encephalopathy.

Estimate creatinine clearance with the Cockcroft–Gault equation for drug-dosing contexts.

Calculate corrected (adjusted) age for preterm infants used in growth and developmental assessment.

Estimate albumin-corrected serum calcium for hypoalbuminemic patients.

Adjust total phenytoin concentration for hypoalbuminemia using the Sheiner–Tozer equation.

Correct the QT interval for heart rate using Bazett or Fridericia formulas.

Correct the reticulocyte percentage for anemia severity using hematocrit.

Correct measured sodium for hyperglycemia using Katz (1.6) or Hillier (2.4) factors.

Stratify community-acquired pneumonia severity and site-of-care decisions using CURB-65.

Calculate estimated due date and current estimated gestational age from the first day of the last menstrual period.

Estimate glomerular filtration rate with the race-free CKD-EPI 2021 creatinine equation and view CKD stage banding.

Calculate fractional excretion of sodium to help differentiate prerenal from intrinsic AKI patterns.

Estimate free water deficit in hypernatremia for replacement planning.

Screen and monitor generalized anxiety symptom severity with GAD-7.

Score eye, verbal, and motor responses for rapid neurologic assessment in trauma and critical care.

Risk-stratify upper GI bleeding for need for intervention and safe outpatient management.

Estimate major bleeding risk in patients on anticoagulation for atrial fibrillation.

Risk-stratify ED chest pain for short-term major adverse cardiac events using HEART.

Estimate insulin resistance from fasting glucose and insulin (HOMA-IR).

Calculate Devine ideal body weight, adjusted body weight, and estimated lean body weight.

Convert mcg/kg/min or mg/kg/h infusions and bag concentration into mL/h pump rates.

Estimate LDL-C from total cholesterol, HDL, and triglycerides using Friedewald.

Estimate hourly and daily maintenance IV fluid rates with the Holiday–Segar / 4-2-1 rule.

Compute mean arterial pressure from systolic and diastolic blood pressure.

Calculate MELD and sodium-adjusted MELD-Na for chronic liver disease severity.

Convert a mg/kg dose and patient weight into a total milligram dose and optional volume.

Apply NEXUS low-risk criteria to help decide whether cervical spine imaging is needed after trauma.

Decide whether ankle or foot radiographs are indicated after acute blunt injury using Ottawa rules.

Estimate pediatric endotracheal tube internal diameter and approximate oral insertion depth from age.

Estimate pediatric weight from age using APLS, Luscombe & Owens, and Best Guess formulas — plus infant and neonate modes.

Apply the PERC rule to help rule out pulmonary embolism in low-risk patients.

Screen and monitor depression symptom severity with the Patient Health Questionnaire-9.

Quick bedside screen for patients with suspected infection at higher risk of poor outcomes.

Estimate pediatric GFR with the Schwartz bedside equation (k × height / creatinine).

Calculate serum osmolality and optional osmolar gap for toxic alcohol and hyperosmolar workups.

Estimate sodium deficit for hyponatremia replacement planning.

Estimate risk in unstable angina / NSTEMI using the TIMI risk score.

Estimate pretest probability of lower-extremity deep vein thrombosis with the Wells DVT criteria.

Estimate pretest probability of pulmonary embolism with the Wells PE criteria.