Sepsis Calculator: Sepsis-3 Criteria

Screen suspected infection with qSOFA vital signs and a six-system SOFA organ dysfunction score.

Sepsis-3 assessment

Enter current clinical measurements. This educational score does not replace urgent clinical evaluation.

Respiratory Rate (breaths/min)

Systolic Blood Pressure (mmHg)

PaO2/FiO2 Ratio

Platelet Count (10^3/mcL)

Bilirubin (mg/dL)

Mean Arterial Pressure (mmHg)

Glasgow Coma Scale

Creatinine (mg/dL)

About the Sepsis-3 calculator

Sepsis is life-threatening organ dysfunction caused by a dysregulated response to infection. The Sepsis-3 framework moved away from systemic inflammatory response criteria and emphasizes a change in Sequential Organ Failure Assessment, commonly called SOFA. In a patient with suspected infection, an acute SOFA increase of two or more points supports the identification of organ dysfunction associated with sepsis. The score should always be interpreted alongside examination, laboratory trends, source evaluation, treatment response, and the patient’s baseline function. This calculator combines two related assessments. The quick SOFA, or qSOFA, screen assigns one point each for a respiratory rate of at least 22 breaths per minute, systolic blood pressure of 100 mmHg or less, and altered mentation. A total of two or three identifies patients outside intensive care who may have a greater risk of poor outcomes. qSOFA is a prompt for closer assessment, not a diagnostic rule, and a low result must never delay cultures, antimicrobials, fluids, source control, or escalation when clinical concern is high. The SOFA portion evaluates respiratory, coagulation, liver, cardiovascular, neurologic, and renal systems. This implementation uses the PaO2 to FiO2 ratio, platelet count, bilirubin, mean arterial pressure, Glasgow Coma Scale, and creatinine. Standard thresholds contribute zero to four points per organ. Full bedside SOFA scoring can additionally account for respiratory support, vasopressor dose, and urine output; clinicians should use complete source data and institutional systems for treatment decisions. Missing measurements should be obtained rather than guessed, and each value should represent the patient’s clinically relevant condition at the time being assessed. Interpret changes over time rather than viewing one number in isolation. Establish the best available baseline, repeat observations when physiology changes, and document assumptions such as sedation effects or chronic kidney disease. Septic shock requires clinical criteria beyond these fields, including persistent vasopressor-dependent hypotension and elevated lactate despite adequate volume resuscitation. If sepsis is possible, activate the appropriate emergency pathway immediately.

Sepsis score examples

Clinical pattern	Scores	Interpretation
RR 18, SBP 120, normal mentation and normal organ values	qSOFA 0, SOFA 0	No threshold is crossed, but clinical assessment continues.
RR 24, SBP 90, normal mentation and normal organ values	qSOFA 2, SOFA 0	Two qSOFA criteria prompt urgent organ dysfunction evaluation.
PaO2/FiO2 250, platelets 90, bilirubin 2.5, GCS 12	SOFA 8 before other points	Multiple organ systems contribute to a high score.

How to calculate sepsis scores

Enter the latest respiratory rate, blood pressure, oxygenation ratio, laboratory values, MAP, and GCS.
Toggle altered mental status when the patient has an acute change from baseline.
Select Calculate Sepsis Scores to apply qSOFA and SOFA thresholds.
Interpret the scores with baseline organ function, infection likelihood, and current clinical trajectory.
Escalate suspected sepsis immediately according to local emergency protocols.

Frequently asked questions

Does a qSOFA score of 2 diagnose sepsis?

No. A score of 2 or more flags increased risk and should prompt evaluation for organ dysfunction. Sepsis remains a clinical diagnosis requiring suspected infection and a meaningful organ dysfunction assessment.

Can a low qSOFA score rule out sepsis?

No. qSOFA has limited sensitivity and a patient with a low score may still be septic. Do not delay investigation or treatment when symptoms, examination, or laboratory findings are concerning.

What SOFA change supports Sepsis-3 organ dysfunction?

An acute increase of at least two SOFA points in the setting of suspected infection supports sepsis-associated organ dysfunction. The baseline is often assumed to be zero only when preexisting organ dysfunction is not known.

Does this calculator diagnose septic shock?

No. Septic shock uses additional criteria, including vasopressors needed to maintain MAP and an elevated lactate after adequate fluid resuscitation. It requires immediate clinician-led assessment and management.

Why can the bedside score differ from this result?

A complete SOFA score accounts for details such as mechanical ventilation, vasopressor dose, and urine output. Sedation, chronic disease, units, timing, and local laboratory conventions can also change the appropriate score.