Centor Score Calculator

Strep throat probability.

Score (/5) 3
Strep probability ~25%
Step-by-step with your numbers:
1. Values used:
2. Age = 0
3. Fever > 38°C = 1
4. Tonsillar exudate = 1
5. Tender anterior cervical nodes = 1
6. Cough present = 0
7. Score = 3/5
8. Strep probability = ~25%
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Centor criteria estimate strep throat probability. Not a diagnosis.

How the Math Works

The Centor Score Calculator uses a clinical scoring system based on four key symptoms: fever, tonsillar exudates, tender anterior cervical lymphadenopathy, and absence of cough. Each present symptom adds 1 point to the total score, ranging from 0 to 4. This score estimates the probability of group A Streptococcus (GABHS) strep throat through established medical guidelines: scores of 0-1 indicate low probability (possibly <10%), scores of 2-3 suggest moderate probability (around 10-35%), and a score of 4 indicates high probability (approximately 50-60%).

Practical Applications

To apply this calculator, count how many of the four Centor criteria are present in a patient with sore throat. Enter each symptom as present or absent, and the calculator will sum the points and provide the corresponding probability range. This helps clinicians decide whether to pursue a rapid strep test or throat culture, and whether antibiotic treatment is warranted based on evidence-based medical guidelines.

Day-to-Day Use

In your daily life, this calculator helps you understand whether your sore throat is likely caused by strep bacteria or a common viral infection. If you get a high score, it might explain severe symptoms and help you decide whether to seek medical care promptly. Knowing your probability helps you avoid unnecessary antibiotic use while ensuring you get appropriate treatment for bacterial infections, potentially preventing complications like rheumatic fever.

FAQ

Test needed?

Score ≥3 often prompts a rapid strep test. See a doctor.