Critical Care Scores

Sequential Organ Failure Assessment (SOFA) Calculator

Scores dysfunction of six organ systems from 0 to 24; an acute rise of 2 or more with infection defines sepsis (Sepsis-3).

Reviewed by Alex G, BSN, RN, CEN, CCRN, CMC, NREMT-P · From the Reference tab of the app

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Formula

Six systems, 0–4 points each, total 0–24
Respiration, PaO₂/FiO₂: under 400 +1, under 300 +2, under 200 with respiratory support +3, under 100 with respiratory support +4
Coagulation, platelets ×10³/µL: under 150 +1, under 100 +2, under 50 +3, under 20 +4
Liver, bilirubin mg/dL: 1.2–1.9 +1, 2.0–5.9 +2, 6.0–11.9 +3, 12.0 or more +4
Cardiovascular: MAP under 70 +1; dopamine ≤5 or any dobutamine +2; dopamine >5, epinephrine ≤0.1 or norepinephrine ≤0.1 +3; dopamine >15, epinephrine >0.1 or norepinephrine >0.1 +4 (mcg/kg/min for at least 1 hour)
CNS, GCS: 13–14 +1, 10–12 +2, 6–9 +3, under 6 +4
Renal, creatinine mg/dL: 1.2–1.9 +1, 2.0–3.4 +2, 3.5–4.9 or urine under 500 mL/day +3, 5.0 or more or urine under 200 mL/day +4
Sepsis-3: sepsis = infection with an acute rise in SOFA of 2 or more from baseline

How it is used

• Sepsis-3: in suspected infection, an acute rise of 2 or more points defines organ dysfunction (sepsis); assume a baseline of 0 when no earlier organ dysfunction is known; a score of 2 or more carries about 10% hospital mortality (Singer 2016).
• Septic shock: vasopressors needed to keep MAP 65 mm Hg or more and lactate over 2 mmol/L despite adequate fluids; hospital mortality over 40% (Singer 2016).
• Designed to describe organ dysfunction over time rather than to predict one patient’s death; vasopressor points count only after at least 1 hour of infusion (Vincent 1996).
• SOFA-2 (Ranzani 2025) revises the thresholds and adds modern organ support; it is still being validated, and Sepsis-3 uses the original score shown here.

Key points

• In suspected infection, a rise of 2 or more points is sepsis: escalate now, with antibiotics within 1 hour for possible septic shock or likely sepsis (SSC 2021).

Same formula as the app. Open it in the web app.

Related one-pagers

• Sepsis and Septic Shock BundleSepsis · Suspected or confirmed infection plus acute SOFA rise ≥2
• Obstetric EmergenciesSepsis complicates about 1 in 1,000 pregnancies and caused 24% of in-hospital maternal deaths (Bauer and Pacheco 2025). Most sources are genitourinary (intraamniotic infection, endometritis, pyelonephritis), then pneumonia, wounds and necrotizing infection; group A streptococcus can reach toxic shock within hours. Normal pregnancy blurs SIRS and SOFA, and qSOFA found only 36–50% of cases, so use maternal early warning criteria and treat unexplained organ dysfunction with infection as sepsis, fever or not (SMFM #47).
• Mass Casualty Triage and Incident CommandThe IOM (2009) defines crisis standards of care as a substantial change in usual operations and the level of care possible, made necessary by a pervasive or catastrophic disaster and formally declared by a state government. Its ethical base is fairness, the duty to care, the duty to steward resources, transparency, consistency, proportionality and accountability. A triage officer or team applies written criteria so bedside clinicians do not allocate, which limits bias and moral distress. The Ontario protocol (Christian, CMAJ 2006) used SOFA-based criteria, reassessed at 48 and 120 hours, and coded blue the patients who should not receive critical care.
• Bleeding, Reversal, HIT and DICIn sepsis, the sepsis-induced coagulopathy (SIC) score flags the earlier phase: platelets 100,000–149,000 (1 point) or under 100,000 (2), INR over 1.2–1.4 (1) or over 1.4 (2), four-organ SOFA 1 (1) or 2 or more (2); 4 or more, with platelet plus INR points above 2, is SIC (ISTH 2019, kept in 2025).

Related calculators

• National Early Warning Score 2 (NEWS2)
• Pneumonia Severity Score (CURB-65)

For education and exam preparation only. Follow your institution’s protocols. For education and exam preparation only. Verify results independently and follow your institution’s protocols. Not a substitute for clinical judgment.