CHA2DS2-VASc Calculator
Use this tool to estimate stroke risk in patients with atrial fibrillation. Enter patient details, then click calculate.
Educational use only. This calculator does not replace professional clinical judgment.
What is the CHA2DS2-VASc score?
The CHA2DS2-VASc score is a clinical risk stratification tool used to estimate the yearly risk of stroke in patients with non-valvular atrial fibrillation (AF). You may also hear people search for this as a “CHADS2 VASc score calculator,” although CHA2DS2-VASc is the expanded and more commonly used framework in modern care.
By assigning points for specific risk factors, clinicians can quickly categorize stroke risk and help guide decisions about anticoagulation therapy.
Scoring criteria at a glance
- C – Congestive heart failure / LV dysfunction: 1 point
- H – Hypertension: 1 point
- A2 – Age 75 years or older: 2 points
- D – Diabetes mellitus: 1 point
- S2 – Prior stroke, TIA, or thromboembolism: 2 points
- V – Vascular disease (MI, PAD, aortic plaque): 1 point
- A – Age 65 to 74 years: 1 point
- Sc – Sex category female: 1 point
How to use this calculator
Step 1: Enter age and sex category
Age contributes automatically: 2 points for 75+, 1 point for 65–74, and 0 points if younger than 65.
Step 2: Select comorbidities
Check each condition that applies. The tool sums all selected point values instantly when you press calculate.
Step 3: Review the interpretation
You will see a total score, an estimated annual stroke risk, and a general risk interpretation. Final treatment choices should always be individualized.
CHADS2 vs CHA2DS2-VASc
The older CHADS2 score includes fewer risk variables and can miss some patients at meaningful risk. CHA2DS2-VASc expands the model to better identify lower-to-intermediate risk individuals, particularly those with vascular disease, age 65–74, and sex-related risk considerations.
In many current guidelines, CHA2DS2-VASc is preferred for stroke risk assessment in non-valvular AF.
Clinical interpretation basics
- Lower scores: Often associated with lower annual stroke risk.
- Intermediate scores: May support shared decision-making about anticoagulation.
- Higher scores: Typically indicate stronger consideration for oral anticoagulation unless contraindicated.
Risk-benefit analysis should include bleeding risk, patient values, kidney/liver function, medication interactions, and prior bleeding history.
Important limitations
- This score estimates population-level risk, not a guaranteed individual outcome.
- Stroke prevention decisions should not rely on one number alone.
- Guidelines evolve; always verify with local protocols and up-to-date society recommendations.
Frequently asked questions
Is this calculator only for atrial fibrillation?
Yes. CHA2DS2-VASc is primarily used for stroke risk stratification in atrial fibrillation patients without moderate-to-severe mitral stenosis or mechanical valves.
Does female sex always mean automatic anticoagulation?
No. Female sex alone (without other risk factors) is generally not treated the same as multiple combined risk factors. Clinical context matters.
Should I use this tool for self-treatment decisions?
No. Use this as an educational aid. Diagnosis and treatment choices should be made with a qualified clinician.