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Stroke Risk Calculator (CHA₂DS₂-VASc)

Estimate your annual stroke risk in atrial fibrillation using the CHA₂DS₂-VASc score (Lip et al. 2010, ESC guideline 2020).

Instructions

Enter your age and sex, then check every risk factor that applies. The CHA₂DS₂-VASc score ranges from 0 to 9 — higher scores mean higher annual stroke risk.

Risk factors

Annual stroke risk by CHA₂DS₂-VASc score

ScoreAnnual riskRecommendation
00.2 %No OAC
10.6 %Consider OAC
22.2 %OAC recommended
33.2 %OAC recommended
44.8 %OAC recommended
57.2 %OAC recommended
69.7 %OAC recommended
711.2 %OAC recommended
810.8 %OAC recommended
912.2 %OAC recommended

How it works

The CHA₂DS₂-VASc score (Lip et al. 2010) is the international standard for stroke risk stratification in non-valvular atrial fibrillation. It assigns points for congestive heart failure (1), hypertension (1), age ≥ 75 (2), diabetes (1), prior stroke or TIA (2), vascular disease (1), age 65–74 (1) and female sex (1). Annual stroke rates were derived from a Swedish AF cohort (Friberg et al., Eur Heart J 2012, n = 90,490). The 2020 ESC guideline recommends oral anticoagulation from a score of 2 in men and 3 in women.

This calculator is for informational purposes only and does not replace medical advice. The decision to anticoagulate must always be made by a clinician weighing the bleeding risk (HAS-BLED score). The score applies only to non-valvular atrial fibrillation.

Frequently Asked Questions

What is the CHA₂DS₂-VASc score?+
The CHA₂DS₂-VASc score (Lip et al. 2010) is a clinical scoring system that estimates annual stroke risk in patients with atrial fibrillation. It ranges from 0 to 9 points, derived from eight clinical risk factors including age, sex, and cardiovascular comorbidities.
When should anticoagulation be started?+
Per the 2020 ESC guideline: in men from a score of 2, in women from a score of 3. With a score of 1 (men) or 2 (women) anticoagulation may be considered after individual benefit-risk assessment including bleeding risk.
Why do women get an extra point?+
Female sex is associated with a slightly higher stroke risk in atrial fibrillation. However, female sex alone (score = 1 from sex only) is not an indication for anticoagulation — at least one additional risk factor must be present.
Which anticoagulant is first line?+
Direct oral anticoagulants (DOACs / NOACs) such as apixaban, rivaroxaban, edoxaban or dabigatran are first-line per the 2020 ESC guideline — except for mechanical heart valves or moderate-to-severe mitral stenosis, where warfarin (VKA) remains required.
How high is stroke risk without treatment?+
In atrial fibrillation with a CHA₂DS₂-VASc score of 4 the annual stroke risk is around 4.8 %, at a score of 7 it rises to roughly 11 %. Adequate anticoagulation reduces this risk by about 64 %.
Should bleeding risk also be assessed?+
Yes. Before any anticoagulation the HAS-BLED score should also be calculated to estimate bleeding risk. A high HAS-BLED is not a contraindication but a flag to address modifiable risk factors (blood pressure, alcohol, concomitant medication).

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Background

Stroke Risk Calculator (CHA₂DS₂-VASc) for Atrial Fibrillation

9 min