Medical Calculators
Free, evidence-based clinical calculators with interpretation guidance. All formulas are referenced from peer-reviewed literature and clinical guidelines.
Renal
2 tools
General
3 tools
BMI
Calculate Body Mass Index (BMI) with WHO classification. Includes interpretation for adults and clinical considerations.
Corrected Ca
Calculates albumin-corrected calcium to estimate true calcium levels in patients with hypoalbuminemia.
MME Calculator
Calculate total daily morphine milligram equivalents (MME) to assess opioid overdose risk. Based on CDC opioid prescribing guidelines.
Mental Health
2 tools
PHQ-9
Patient Health Questionnaire-9 (PHQ-9) for depression screening and severity assessment. Validated tool for clinical use.
GAD-7
Generalized Anxiety Disorder 7-item (GAD-7) scale for anxiety screening and severity assessment. Validated clinical tool.
Cardiovascular
7 tools
Framingham
Free Framingham 10-year cardiovascular risk calculator. Age, sex, lipids, BP, smoking, diabetes estimate CHD risk and guide statin therapy decisions.
CHA₂DS₂-VASc
Calculates stroke risk in patients with atrial fibrillation to guide anticoagulation therapy decisions. Recommended by ACC/AHA/ESC guidelines.
Wells DVT
Calculates the probability of deep vein thrombosis (DVT) using the Wells criteria to guide diagnostic testing decisions.
ASCVD Risk
Calculates 10-year atherosclerotic cardiovascular disease (ASCVD) risk using the ACC/AHA Pooled Cohort Equations to guide statin therapy decisions.
HAS-BLED
Calculates bleeding risk in patients with atrial fibrillation on anticoagulation to help guide therapy decisions alongside stroke risk assessment.
Wells PE
Calculates the pre-test probability of pulmonary embolism (PE) using the Wells criteria to guide diagnostic testing decisions.
QTc
Calculates corrected QT interval (QTc) using multiple formulas to assess risk of torsades de pointes and guide medication management.
Emergency
10 tools
TIMI Score
Free TIMI risk score for unstable angina/NSTEMI. 7 criteria predict 14-day MACE risk and guide invasive vs conservative management decisions.
HEART Score
Free HEART score for chest pain in the ED. History, ECG, age, risk factors, troponin to risk-stratify MACE at 6 weeks. Guides admit vs discharge.
PERC Rule
Free PERC rule calculator. 8 criteria to safely rule out PE in low-risk ED patients without D-dimer. Validated for under 2% pretest probability.
NIHSS
Free NIHSS stroke scale calculator. Score all 15 items for acute ischemic stroke severity (0-42). Guides tPA decisions and stroke center transfers.
qSOFA
Free qSOFA calculator (Sepsis-3). Score altered mentation, RR ≥22, SBP ≤100 to flag sepsis risk outside the ICU. ≥2 = increased mortality risk.
SOFA Score
Free SOFA score calculator. Quantify organ failure across 6 systems (resp, coag, liver, CV, CNS, renal) to track ICU mortality risk in sepsis.
APACHE II
Free APACHE II score calculator. 12 physiologic variables plus age and chronic health to predict ICU mortality. Used within 24h of admission.
Ottawa Ankle Rules
Free Ottawa Ankle Rules calculator. Determine if ankle/foot X-rays are needed after injury. ~100% sensitivity for clinically significant fractures.
Ottawa Knee Rule
Free Ottawa Knee Rule calculator. 5 criteria to determine if a knee X-ray is needed after acute injury. ~100% sensitivity for clinically important fx.
Parkland Formula
Free Parkland formula calculator for burn fluid resuscitation. 4 mL x kg x %TBSA over 24h, half in the first 8h. Includes urine output goals.
Clinical Disclaimer
These calculators are provided for educational and clinical decision support purposes only. Results should be interpreted in the context of individual patient circumstances. Always use clinical judgment and consult relevant guidelines. These tools do not replace professional medical advice, diagnosis, or treatment.
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