The Sequential Organ Failure Assessment, or SOFA, is the standard bedside score for tracking multi-organ dysfunction in critically ill patients. It underpins the Sepsis-3 definition and helps intensivists follow a patient’s trajectory day by day. This calculator scores all six organ systems and returns the total with an approximate mortality band, computed in your browser.
How it works
Each of six organ systems is scored from 0 (normal) to 4 (most severe) using the published cut-offs, then summed:
total = respiration + coagulation + liver
+ cardiovascular + CNS + renal (each 0–4, total 0–24)Respiration uses the P/F ratio, coagulation uses the platelet count, liver uses bilirubin, cardiovascular uses mean arterial pressure and vasopressor dose, CNS uses the Glasgow Coma Scale, and renal uses creatinine or urine output. The dropdowns map your selection straight to the correct subscore.
Scoring reference for all six systems
| System | Variable | Score 0 | Score 1 | Score 2 | Score 3 | Score 4 |
|---|---|---|---|---|---|---|
| Respiration | P/F ratio (mmHg) | ≥400 | 300–399 | 200–299 | 100–199 on vent | <100 on vent |
| Coagulation | Platelets (×10³/µL) | ≥150 | 100–149 | 50–99 | 20–49 | <20 |
| Liver | Bilirubin (mg/dL) | <1.2 | 1.2–1.9 | 2.0–5.9 | 6.0–11.9 | ≥12.0 |
| Cardiovascular | MAP / pressors | MAP ≥70 | MAP <70 | Low-dose DA or dobutamine | DA >5 or any epi/norepi | DA >15 or high epi/norepi |
| CNS | Glasgow Coma Scale | 15 | 13–14 | 10–12 | 6–9 | <6 |
| Renal | Creatinine (mg/dL) | <1.2 | 1.2–1.9 | 2.0–3.4 | 3.5–4.9 or UO <500 mL/d | ≥5.0 or UO <200 mL/d |
Use the worst value recorded during that 24-hour period for each system.
SOFA in the Sepsis-3 definition
The Sepsis-3 consensus (2016) defined sepsis as suspected or confirmed infection plus an acute SOFA increase of 2 or more points from the patient’s pre-illness baseline (assumed to be zero in patients without prior organ dysfunction). This makes the change in score as important as the absolute value — two patients with a SOFA of 6 may have very different prognoses if one rose from 0 and the other from 5.
The quick SOFA (qSOFA) screen — altered mental status, respiratory rate ≥22, systolic BP ≤100 — is used outside the ICU for rapid identification, but it is not a substitute for SOFA once in the ICU setting.
Worked example and interpretation
A ventilated septic patient: P/F 150 (score 3), platelets 80 (score 2), bilirubin 2.5 mg/dL (score 2), low-dose noradrenaline (score 3), GCS 13 (score 1), creatinine 2.2 mg/dL (score 2) → total SOFA = 13.
A total above 11 is associated with high ICU mortality in published cohorts, though mortality bands are study-dependent and should never replace individual clinical judgment. Far more useful than the single value is the trend: a SOFA falling from 13 to 10 to 7 over three days signals organ recovery and typically correlates with improving survival; a rising SOFA demands urgent reassessment of the underlying source and therapy. Score daily at the same time and graph the trajectory.