CURB-65 Score Calculator

Calculate the CURB-65 score for assessing pneumonia severity and guiding decisions about hospitalization. Based on Confusion, Urea, Respiratory rate, Blood pressure, and age 65+. Educational reference only.

🫁 Clinical Reference📐 CURB-65 = Sum of 5 criteria (0-5 points)🏥 Health
Confusion (new onset)
Urea >7 mmol/L (BUN >19 mg/dL)
Respiratory rate ≥30/min
Blood pressure (SBP<90 or DBP≤60)
Age ≥65 years
Please enter valid values.

Formula & Reference

VariableSymbolFormulaUnits
CURB-65 Score CalculatorCURB-65 = Sum of 5 criteria (0-5 points)score 0-5

Step-by-Step Examples

Example 1
Low Risk

No confusion, normal urea, RR<30, normal BP, age<65.

  • Total = 0
  • Low risk category (~0.7% mortality)
  • Outpatient treatment often appropriate with this profile
✓ Score 0 — low risk
Example 2
Moderate Risk

Elevated respiratory rate and age ≥65, other criteria normal.

  • Total = 0+0+1+0+1 = 2
  • Moderate risk category (~9.2% mortality)
  • Often prompts consideration of hospital admission
✓ Score 2 — moderate risk
Example 3
High Risk

Confusion present, elevated urea, low blood pressure, age≥65.

  • Total = 1+1+0+1+1 = 4
  • High risk category (~40% mortality)
  • Strong indication for hospitalization, ICU consideration
✓ Score 4 — high risk

Real-World Applications

Common Mistakes to Avoid

⚠️
Using CURB-65 as the sole determinant of disposition

While useful, clinical judgment must incorporate additional factors (comorbidities, social situation, oxygen saturation, clinical trajectory) beyond the basic score.

⚠️
Confusing CURB-65 with CRB-65

CRB-65 (without urea/blood test) is sometimes used in outpatient settings without lab access — know which version applies to your clinical context.

⚠️
Treating this as providing medical advice for self-assessment

This is an educational reference tool only — pneumonia severity assessment requires evaluation by qualified healthcare providers, not self-diagnosis using this calculator.

Frequently Asked Questions

What does CURB-65 stand for?
Confusion, Urea (elevated), Respiratory rate (≥30/min), Blood pressure (low), and Age (≥65 years) — five clinical criteria scored to assess pneumonia severity.
How is CURB-65 used clinically?
Score guides disposition decisions: low scores (0-1) often support outpatient management, moderate scores (2) prompt hospitalization consideration, higher scores (3-5) typically indicate need for hospitalization, possibly ICU level care.
What is the difference between CURB-65 and CRB-65?
CRB-65 omits the urea/BUN criterion, making it usable without blood tests — useful in primary care or resource-limited settings where lab results may not be immediately available.
Is CURB-65 perfect for predicting outcomes?
No clinical score is perfect — CURB-65 is a validated decision-support tool but should always be combined with overall clinical judgment, considering factors the score doesn't capture.
What are the mortality risk percentages based on?
Derived from research studies correlating CURB-65 scores with actual patient outcomes — these are population-level statistics, not individual patient predictions.

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