Clinical Toolkit · Free

Every calculator you need, always on you.

Evidence-based clinical calculators for medical students and practitioners. Free, fast, no login required.

Cardiovascular

Mean Arterial Pressure (MAP)

Calculate mean arterial pressure from systolic and diastolic blood pressure.

CardiologyCritical CareGeneral Medicine

QTc Interval (Bazett)

Correct the QT interval for heart rate using the Bazett formula to assess TdP risk.

CardiologyPharmacologyGeneral MedicineCritical Care

CHA₂DS₂-VASc Score

Estimate stroke risk in non-valvular atrial fibrillation to guide anticoagulation.

CardiologyGeneral MedicineHaematology

HAS-BLED Bleeding Risk Score

Estimate major bleeding risk in AF patients on anticoagulation.

CardiologyHaematologyGeneral Medicine

HEART Score

Risk-stratify chest pain patients in the ED for major adverse cardiac events (MACE).

CardiologyEmergency MedicineGeneral Medicine

Framingham 10-Year CVD Risk

Estimate 10-year cardiovascular disease risk using the simplified Framingham points-based model.

CardiologyPreventive MedicineGeneral MedicineEndocrinology

Wells DVT Score

Pre-test probability of deep vein thrombosis to guide D-dimer testing and imaging.

HaematologyGeneral MedicineSurgeryEmergency Medicine

Wells PE Score

Pre-test probability of pulmonary embolism to guide D-dimer and CT-PA decision.

PulmonologyEmergency MedicineHaematologyGeneral Medicine

Caprini VTE Risk Score

Assess VTE risk in surgical patients to guide prophylaxis decisions.

SurgeryCritical CareHaematologyGeneral Medicine

Revised Cardiac Risk Index (RCRI)

Estimate perioperative major adverse cardiac event (MACE) risk before non-cardiac surgery.

CardiologyAnaesthesiaSurgeryGeneral Medicine

Renal Function

Creatinine Clearance (Cockcroft-Gault)

Estimate creatinine clearance for drug dosing and CKD staging using Cockcroft-Gault.

NephrologyPharmacologyGeneral MedicineCritical CareDosing

CKD-EPI GFR (2021)

Estimate GFR using the 2021 race-free CKD-EPI creatinine equation for CKD staging.

NephrologyGeneral MedicineEndocrinology

MDRD GFR (4-Variable)

Estimate GFR using the 4-variable MDRD equation — widely reported by Indian labs.

NephrologyGeneral MedicinePathology

Fractional Excretion of Sodium (FENa)

Distinguish prerenal from intrinsic renal AKI using the fractional excretion of sodium.

NephrologyCritical CareEmergency MedicineGeneral Medicine

Hepatic Function

Child-Pugh Score

Assess severity of liver cirrhosis and estimate surgical risk and prognosis.

GastroenterologyHepatologySurgeryGeneral Medicine

MELD-Na Score

Estimate 90-day liver transplant waitlist mortality and prioritise organ allocation.

GastroenterologyHepatologyTransplantCritical Care

FIB-4 Index

Non-invasive assessment of hepatic fibrosis stage using age, AST, ALT, and platelet count.

GastroenterologyHepatologyGeneral MedicineEndocrinology

Laboratory & Electrolytes

Anion Gap (with Albumin Correction)

Calculate anion gap and albumin-corrected anion gap for acid-base analysis.

NephrologyCritical CareGeneral MedicineEmergency Medicine

Corrected Calcium (for Albumin)

Correct serum calcium for hypoalbuminaemia to identify true hypercalcaemia or hypocalcaemia.

EndocrinologyNephrologyGeneral MedicineCritical Care

Corrected Sodium for Hyperglycaemia

Correct serum sodium for hyperglycaemia-induced dilutional hyponatraemia (e.g., DKA, HHS).

EndocrinologyCritical CareNephrologyEmergency Medicine

Serum Osmolality

Calculate estimated serum osmolality and osmol gap to detect unmeasured osmoles.

NephrologyCritical CareEmergency MedicineToxicology

LDL Cholesterol (Friedewald)

Calculate LDL cholesterol using the Friedewald equation from a standard lipid panel.

CardiologyEndocrinologyPreventive MedicineGeneral Medicine

HOMA-IR (Insulin Resistance)

Estimate insulin resistance using fasting glucose and insulin (Homeostatic Model Assessment).

EndocrinologyDiabetologyGeneral MedicinePreventive Medicine

Free Water Deficit

Calculate free water deficit in hypernatraemia to guide safe rehydration therapy.

NephrologyCritical CareGeneral MedicineEmergency Medicine

Critical Care

SOFA Score

Sequential Organ Failure Assessment — estimates ICU mortality based on 6 organ systems.

Critical CareICUMedicine

Glasgow Coma Scale

Standardised neurological assessment of consciousness — Eye, Verbal, Motor response.

NeurologyCritical CareEmergency

SIRS Criteria

Systemic Inflammatory Response Syndrome — ≥2 criteria define SIRS.

Critical CareInfectionMedicine

APACHE II Score

Acute Physiology and Chronic Health Evaluation II — ICU mortality prediction from 12 physiological variables.

Critical CareICUMedicine

Glasgow-Blatchford Score

Pre-endoscopy risk stratification for upper GI bleeding.

GastroenterologyEmergencyMedicine

Charlson Comorbidity Index

Predicts 10-year mortality based on 19 comorbid conditions plus age.

MedicineOncologySurgery

Respiratory

CURB-65

Community-acquired pneumonia severity score — guides admission vs outpatient decision.

RespiratoryInfectionMedicine

Pneumonia Severity Index (PORT)

Fine et al. risk classification for CAP — 20-variable score predicting 30-day mortality.

RespiratoryInfectionMedicine

PERC Rule

Pulmonary Embolism Rule-out Criteria — 8-item rule to exclude PE without testing.

RespiratoryEmergencyMedicine

Infection

Centor Score (Modified McIsaac)

Predicts likelihood of Group A Streptococcal pharyngitis — guides antibiotic use.

InfectionENTMedicine

FeverPAIN Score

Predicts Group A Streptococcal throat infection — UK guideline-endorsed alternative to Centor.

InfectionENTMedicine

Fluids & Medications

Maintenance Fluid Calculator

Calculates daily and hourly maintenance fluid requirements using the Holliday-Segar method.

PaediatricsCritical CareMedicine

Steroid Conversion Calculator

Converts between equivalent anti-inflammatory doses of corticosteroids.

PharmacologyMedicineRheumatology

Morphine Milligram Equivalent (MME)

Calculates daily opioid dose in morphine equivalents for safety monitoring.

PharmacologyPain ManagementMedicine

Obstetrics

Estimated Due Date (Naegele's Rule)

Calculates estimated due date from last menstrual period.

ObstetricsGynaecology

Gestational Age Calculator

Calculates current gestational age from the last menstrual period.

ObstetricsGynaecology

Estimated Conception Date

Estimates date of conception from last menstrual period (assuming 28-day cycle).

ObstetricsGynaecology

Oncology

Lung Cancer TNM Staging

Simplified NSCLC TNM staging (8th edition IASLC) with 5-year survival estimates.

OncologyRespiratorySurgery

“Wherever the art of medicine is loved, there is also a love of humanity.” — Hippocrates