CURB-65 Calculator

Score pneumonia severity with CURB-65 (confusion, urea, respiratory rate, blood pressure, age 65 or older) to estimate 30-day mortality. Example: a 70-year-old with a raised urea and no other criteria scores 2, with about 6.8% 30-day mortality.

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New confusion

Urea above 7 mmol/L (BUN above 19 mg/dL)

Respiratory rate 30 or more per minute

Systolic BP below 90 or diastolic BP 60 or less

Age 65 or older

How to use the CURB-65 Calculator

Enter the values in the fields.
Press Calculate to see the result with the steps shown.

Formula and method

CURB-65 = confusion (1) + urea above 7 mmol/L (1) + respiratory rate 30 or more (1) + systolic BP below 90 or diastolic 60 or less (1) + age 65 or older (1).

CURB-65 and mortality

Score	30-day mortality	Suggested setting
0	0.6%	Outpatient
1	2.7%	Outpatient
2	6.8%	Short stay / supervised
3	14.0%	Hospital, consider ICU
4	27.8%	Hospital, ICU
5	27.8%	Hospital, ICU

Units for urea

Urea 7 mmol/L is about 19 mg/dL of BUN. The calculator uses the 7 mmol/L threshold.

CRB-65

If urea is not available, CRB-65 (drop the U) is often used in the community.

Cautions

This calculator is for education and is not medical advice. Decisions about diagnosis and treatment belong with a qualified clinician.

Frequently asked questions

What does CURB-65 stand for?

Confusion, Urea, Respiratory rate, Blood pressure, age 65.

What score needs hospital care?

2 or more is usually considered for admission.

Does it replace clinical judgement?

No.

Is it for COVID-19?

It was designed for community-acquired pneumonia.

What is CRB-65?

The version without urea.

What is the maximum score?

Sources

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Effortless Math Team

11 minutes ago