liminfoCHA2DS2-VASc Calculator
Free web tool: CHA2DS2-VASc Calculator
CHA2DS2-VASc Score
0 / 9
Annual Stroke Risk
0%
Recommendation
No anticoagulation recommended
| Score | Annual Stroke Risk |
|---|---|
| 0 | 0% |
| 1 | 1.3% |
| 2 | 2.2% |
| 3 | 3.2% |
| 4 | 4.0% |
| 5 | 6.7% |
| 6 | 9.8% |
| 7 | 9.6% |
| 8 | 12.5% |
| 9 | 15.2% |
CHA2DS2-VASc for atrial fibrillation stroke risk. For clinical reference only.
About CHA2DS2-VASc Calculator
The CHA2DS2-VASc Calculator is a free, browser-based clinical reference tool for computing the CHA2DS2-VASc stroke risk score in patients with non-valvular atrial fibrillation (AF). CHA2DS2-VASc is the widely validated scoring system recommended by ACC/AHA, ESC, and most major cardiology guidelines for stratifying stroke risk in AF patients and guiding anticoagulation therapy decisions. The score stands for: Congestive heart failure (1 point), Hypertension (1 point), Age ≥75 years (2 points), Diabetes mellitus (1 point), Stroke/TIA/thromboembolism history (2 points), Vascular disease such as prior MI or PAD (1 point), Age 65–74 (1 point), and Sex category female (1 point) — maximum 9 points.
To use the calculator, check each risk factor that applies to the patient. The score updates instantly, and the tool displays three outputs: the total CHA2DS2-VASc score out of 9, the corresponding annual stroke risk percentage (from validated clinical data: 0% at score 0 up to 15.2% at score 9), and the treatment recommendation — no anticoagulation at score 0, consider anticoagulation at score 1, and oral anticoagulation recommended at score 2 or higher. A reference table showing all score-to-risk mappings is displayed below the inputs for easy review.
This tool is intended for clinical reference by healthcare professionals. It is not a substitute for clinical judgment, and treatment decisions should always consider the patient's individual bleeding risk, preferences, and comorbidities. CHA2DS2-VASc is used alongside HAS-BLED and other bleeding risk scores in practice. All calculations run entirely within your browser — no patient data is ever transmitted to any server, making this tool safe for use in clinical environments.
Key Features
- All 8 CHA2DS2-VASc criteria as interactive checkboxes with point values clearly labeled
- Real-time score calculation updating instantly as criteria are checked or unchecked
- Annual stroke risk percentage from validated clinical data (0% to 15.2% and beyond)
- Color-coded treatment recommendation: green (no anticoagulation), yellow (consider), red (recommended)
- Full reference table showing stroke risk for every score level (0–9) for quick comparison
- Correct point weighting: Age ≥75 and Stroke/TIA history each count as 2 points
- 100% client-side processing — no patient data ever leaves your browser
- Dark mode support and clean clinical layout for professional use
Frequently Asked Questions
What does CHA2DS2-VASc stand for?
CHA2DS2-VASc is an acronym for the 8 risk factors in the scoring system: C = Congestive heart failure (1 pt), H = Hypertension (1 pt), A2 = Age ≥75 (2 pts), D = Diabetes mellitus (1 pt), S2 = Stroke/TIA/thromboembolism history (2 pts), V = Vascular disease such as prior MI, peripheral artery disease, or aortic plaque (1 pt), A = Age 65–74 (1 pt), Sc = Sex category female (1 pt). Maximum total is 9 points.
Why does the score go up to 9 instead of 8?
Two of the criteria — Age ≥75 and prior Stroke/TIA/thromboembolism — each contribute 2 points instead of 1. This reflects their stronger association with stroke risk compared to the other risk factors. The remaining 6 criteria each contribute 1 point, giving a maximum total of 2+2+6 = 10... however the Sex category (female) is only counted if at least one other risk factor is present, so the effective maximum usable score is 9.
What annual stroke risk does each score correspond to?
Based on validated clinical data: Score 0 = 0%, Score 1 = 1.3%, Score 2 = 2.2%, Score 3 = 3.2%, Score 4 = 4.0%, Score 5 = 6.7%, Score 6 = 9.8%, Score 7 = 9.6%, Score 8 = 12.5%, Score 9 = 15.2%. These figures represent annual ischemic stroke rates observed in AF cohorts without anticoagulation.
What does the treatment recommendation mean?
Score 0: No anticoagulation is recommended (low stroke risk, anticoagulation risks outweigh benefits). Score 1: Consider anticoagulation — guidelines suggest oral anticoagulant or aspirin may be appropriate depending on patient preferences and bleeding risk. Score 2 or higher: Oral anticoagulation is recommended — options include warfarin (target INR 2–3) or novel oral anticoagulants (NOACs) such as apixaban, rivaroxaban, dabigatran, or edoxaban.
Is a female sex score always added?
Current guidelines (ESC 2020, ACC/AHA) indicate that female sex (Sc) adds 1 point but should not be counted as an independent risk factor when the total score from all other factors is 0. In other words, a score of 1 based solely on female sex should be treated similarly to a score of 0. This calculator includes the female sex criterion as a checkbox consistent with the original scoring framework; clinicians should apply guideline-specific interpretation.
How often should CHA2DS2-VASc be reassessed?
CHA2DS2-VASc should be reassessed at least annually and whenever a patient's clinical status changes — such as a new stroke, development of heart failure, new diabetes diagnosis, or reaching age 65 or 75. Risk factors that increase the score (like age milestones) are cumulative and do not resolve, so the score generally increases over time.
Should I use CHA2DS2-VASc alone to decide on anticoagulation?
No. CHA2DS2-VASc quantifies stroke risk, but anticoagulation decisions must also consider bleeding risk (typically assessed with HAS-BLED score), patient preferences, renal function, other medications, and clinical judgment. This tool is intended as a clinical reference to support — not replace — physician decision-making. Always consult current cardiology guidelines and the individual patient's full clinical picture.
Is this calculator free to use?
Yes, the CHA2DS2-VASc Calculator is completely free with no usage limits and no account required. No patient data is ever transmitted to a server — all calculations run locally in your browser, making it safe for clinical environments.