Important Clinical Disclaimer: SOFA Score Calculator is intended for use by qualified healthcare professionals only. It is for educational and informational purposes and should not replace clinical judgement. Always interpret results alongside the full clinical picture and follow your local guidelines and protocols.

Respiration (PaO₂/FiO₂ ratio)

≥400 mmHg (53.3 kPa) 0 points

<400 mmHg (53.3 kPa) 1 point

<300 mmHg (40 kPa) 2 points

<200 mmHg (26.7 kPa) with respiratory support 3 points

<100 mmHg (13.3 kPa) with respiratory support 4 points

PaO₂/FiO₂ ratio (P/F ratio). Respiratory support = mechanical ventilation including CPAP.

Coagulation (Platelets)

≥150 × 10³/μL 0 points

<150 × 10³/μL 1 point

<100 × 10³/μL 2 points

<50 × 10³/μL 3 points

<20 × 10³/μL 4 points

Liver (Bilirubin)

<20 μmol/L (1.2 mg/dL) 0 points

20-32 μmol/L (1.2-1.9 mg/dL) 1 point

33-101 μmol/L (2.0-5.9 mg/dL) 2 points

102-204 μmol/L (6.0-11.9 mg/dL) 3 points

>204 μmol/L (12 mg/dL) 4 points

Cardiovascular (Hypotension)

MAP ≥70 mmHg 0 points

MAP <70 mmHg 1 point

Dopamine ≤5 or dobutamine (any dose) 2 points

Dopamine >5, adrenaline ≤0.1, or noradrenaline ≤0.1 3 points

Dopamine >15, adrenaline >0.1, or noradrenaline >0.1 4 points

Vasopressor doses in μg/kg/min for at least 1 hour. MAP = Mean Arterial Pressure.

Central Nervous System (Glasgow Coma Scale)

GCS 15 0 points

GCS 13-14 1 point

GCS 10-12 2 points

GCS 6-9 3 points

GCS <6 4 points

Use GCS Calculator if needed. If sedated, estimate GCS before sedation.

Renal (Creatinine or Urine Output)

<110 μmol/L (1.2 mg/dL) 0 points

110-170 μmol/L (1.2-1.9 mg/dL) 1 point

171-299 μmol/L (2.0-3.4 mg/dL) 2 points

300-440 μmol/L (3.5-4.9 mg/dL) OR UO <500 mL/day 3 points

>440 μmol/L (5.0 mg/dL) OR UO <200 mL/day 4 points

UO = Urine Output. Creatinine-based scoring preferred if available.

Sepsis Assessment (Optional)

Suspected or confirmed infection

Lactate (mmol/L)

Vasopressors required?

For Sepsis-3 septic shock criteria assessment.

Results

SOFA Score

-

out of 24

Estimated Mortality

-

ICU mortality

Based on initial SOFA score

Score Breakdown

Organ System	Score	Status

Clinical Interpretation

This result is for guidance only. Clinical judgement should always take precedence.

About SOFA Score

What is SOFA?

The Sequential Organ Failure Assessment (SOFA) score was developed in 1994 by the European Society of Intensive Care Medicine to describe the degree of organ dysfunction/failure in critically ill patients. Originally called the "Sepsis-related Organ Failure Assessment," it was renamed as it applies to all ICU patients regardless of infection status.

Sepsis-3 Definition (2016)

The Third International Consensus Definitions for Sepsis (Sepsis-3) incorporated SOFA into the definition of sepsis:

Sepsis: Life-threatening organ dysfunction caused by a dysregulated host response to infection, identified by an acute increase in SOFA score of ≥2 points.

Septic Shock: Sepsis with persisting hypotension requiring vasopressors to maintain MAP ≥65 mmHg AND serum lactate >2 mmol/L despite adequate volume resuscitation.

Components

SOFA assesses six organ systems, each scored 0-4 based on degree of dysfunction:

Respiration: PaO₂/FiO₂ ratio
Coagulation: Platelet count
Liver: Bilirubin level
Cardiovascular: Mean arterial pressure and vasopressor requirements
Central Nervous System: Glasgow Coma Scale
Renal: Creatinine or urine output

SOFA Score and Mortality

SOFA Score	ICU Mortality	Interpretation
0-1	<5%	Minimal organ dysfunction
2-3	~10%	Mild organ dysfunction
4-5	~15%	Moderate organ dysfunction
6-7	~20%	Moderate-severe dysfunction
8-9	~35%	Severe organ dysfunction
10-11	~50%	Very severe dysfunction
≥12	>80%	Multi-organ failure, critical

Mortality estimates based on observational studies. Serial SOFA scores (delta-SOFA) may be more predictive than single measurements. An increase in SOFA score during ICU stay is associated with worse outcomes.

Limitations

ICU population: SOFA was developed for and validated in ICU patients; may not apply to other settings
Sedation: GCS component may be unreliable in sedated patients
Chronic conditions: Baseline organ dysfunction may confound scoring
Time sensitivity: Laboratory values may lag behind clinical changes
Single score vs trends: Serial SOFA scores are more informative than a single measurement
Inter-rater variability: Cardiovascular component (vasopressor dosing) may vary between centres

Frequently Asked Questions

The Sequential Organ Failure Assessment (SOFA) score is a scoring system used to track a patient's status in the ICU. It assesses six organ systems (respiratory, cardiovascular, hepatic, coagulation, renal, and neurological) with scores from 0-4 for each, giving a total score of 0-24.

Sepsis-3 (2016) defines sepsis as life-threatening organ dysfunction caused by a dysregulated host response to infection. Organ dysfunction is identified by an acute increase in SOFA score of ≥2 points. Septic shock is defined as sepsis with persisting hypotension requiring vasopressors and lactate >2 mmol/L despite adequate resuscitation.

A SOFA score of 2 or more represents organ dysfunction. Higher scores indicate more severe dysfunction. SOFA ≥2 with suspected infection suggests sepsis. Mortality increases significantly with higher SOFA scores, with scores >11 associated with mortality rates exceeding 50%.

SOFA score should be calculated at ICU admission and then daily (or more frequently if clinical status changes). Serial SOFA scores are valuable for tracking response to treatment - an increasing SOFA suggests deterioration while a decreasing SOFA indicates improvement.

References

Vincent JL, Moreno R, Takala J, et al. The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure. Intensive Care Med. 1996;22(7):707-710. PubMed
Singer M, Deutschman CS, Seymour CW, et al. The Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3). JAMA. 2016;315(8):801-810. PubMed
Ferreira FL, Bota DP, Bross A, et al. Serial evaluation of the SOFA score to predict outcome in critically ill patients. JAMA. 2001;286(14):1754-1758. PubMed
NICE guideline [NG51]: Sepsis: recognition, diagnosis and early management. NICE
Surviving Sepsis Campaign: International Guidelines for Management of Sepsis and Septic Shock 2021. SCCM

Disclaimer

This calculator is provided for educational and informational purposes only. It is not intended to be a substitute for professional medical advice, diagnosis, or treatment.

Always seek the advice of a qualified healthcare provider with any questions regarding a medical condition.
Never disregard professional medical advice or delay seeking it because of information from this tool.
Clinical decision-making should always incorporate the full clinical context, patient preferences, and local protocols.
The creators of this tool accept no liability for decisions made based on its output.

If you are a patient: please discuss any results with your healthcare provider. This tool is designed for use by medical professionals and may not be appropriate for self-assessment.

Quick Reference

SOFA Score Range

Total: 0-24 points
6 organ systems × 0-4 points each
≥2 increase = organ dysfunction

Sepsis-3 Criteria

Sepsis: Suspected infection + SOFA ≥2

Septic Shock: Sepsis + vasopressors for MAP ≥65 + lactate >2 mmol/L

Related Tools

Clinical Pearl

Delta-SOFA (change in SOFA over time) may be more valuable than a single measurement. An increasing SOFA during ICU stay is associated with mortality >50%, while a decreasing SOFA indicates response to treatment and lower mortality.

SOFA Score Calculator