CHA2DS2-VASc Score Calculator
Estimate annual stroke risk in patients with non-valvular atrial fibrillation (AF). Enter age, sex, and risk factors below.
What is the CHA2DS2-VASc score?
The CHA2DS2-VASc score is a clinical tool used to estimate stroke risk in adults with atrial fibrillation. In daily practice, it helps clinicians decide whether oral anticoagulation should be considered to reduce the risk of ischemic stroke and systemic embolism.
The score builds on common cardiovascular risk factors and assigns weighted points to each one. A higher total score indicates a higher annual risk of stroke.
How points are assigned
| Component | Description | Points |
|---|---|---|
| C | Congestive heart failure / left ventricular dysfunction | 1 |
| H | Hypertension | 1 |
| A2 | Age ≥ 75 years | 2 |
| D | Diabetes mellitus | 1 |
| S2 | Prior stroke / TIA / thromboembolism | 2 |
| V | Vascular disease (prior MI, PAD, or aortic plaque) | 1 |
| A | Age 65–74 years | 1 |
| Sc | Sex category (female) | 1 |
Interpreting the result
Interpretation depends on both the total score and sex. General guideline-style thresholds often used are:
- Men: 0 = low risk, 1 = consider anticoagulation, ≥2 = anticoagulation usually recommended.
- Women: 1 (sex alone) = low risk, 2 = consider anticoagulation, ≥3 = anticoagulation usually recommended.
Estimated annual stroke risk by score (approximate)
| CHA2DS2-VASc Score | Estimated Annual Stroke Risk |
|---|---|
| 0 | 0.0% |
| 1 | 1.3% |
| 2 | 2.2% |
| 3 | 3.2% |
| 4 | 4.0% |
| 5 | 6.7% |
| 6 | 9.8% |
| 7 | 9.6% |
| 8 | 6.7% |
| 9 | 15.2% |
Practical clinical notes
1) Age matters a lot
Age contributes heavily to stroke risk. Moving from the 65–74 range to 75+ adds an extra point, reflecting a meaningful shift in risk.
2) Prior stroke/TIA is a major signal
Any prior ischemic neurologic event strongly predicts future events, which is why this item carries 2 points.
3) Female sex as a modifier
Female sex adds one point in the formal score, but sex alone is usually not enough to trigger anticoagulation. It functions more as a risk modifier in the presence of additional factors.
4) Don’t ignore bleeding risk
Stroke prevention and bleeding prevention must be balanced. In many workflows, clinicians pair CHA2DS2-VASc with bleeding-risk assessment tools and a shared decision-making conversation.
Frequently asked questions
Is this score used for valvular AF?
It is primarily applied to non-valvular AF scenarios. Valvular conditions may follow different anticoagulation pathways.
Does this calculator replace medical advice?
No. It is a support tool. Final treatment decisions should be made with a qualified healthcare professional.
Can lifestyle changes lower stroke risk in AF?
Yes—controlling blood pressure, diabetes, weight, sleep apnea, alcohol intake, and smoking status can improve cardiovascular outcomes, but these measures do not automatically replace anticoagulation when indicated.