CHA₂DS₂-VASc Calculator

Reviewed by Hamza Gujjar, Algorithm Architect & Software Developer Last updated: August 20, 2026

Disclaimer: This calculator is provided for informational and educational purposes only and does not constitute financial, medical, legal, or other professional advice. Always consult a qualified professional before making decisions based on these results.

Congestive heart failure / LV dysfunction Hypertension Diabetes mellitus Prior stroke / TIA / thromboembolism Vascular disease (MI, PAD, aortic plaque)

📚 Confused about how this is calculated? Read the full When Medicine Learned to Trust the Checklist →

A Scoring Scheme Named After Its Own Checklist

CHA²DS²-VASc is an acronym that doubles as its own scoring rubric: each letter is a risk factor, and the superscript twos mark the two factors worth double points. Built as a refinement of the earlier CHADS² score, its particular strength is at the low end — it is markedly better at identifying people with atrial fibrillation who are genuinely at low stroke risk, which is a harder and arguably more useful discrimination than flagging the obviously high-risk. This calculator performs the standard point arithmetic and looks up the corresponding published risk figure.

The Scoring

C — Congestive heart failure / LV dysfunction +1
H — Hypertension +1
A² — Age 75 or over +2 (age 65–74 scores +1)
D — Diabetes mellitus +1
S² — Prior stroke / TIA / thromboembolism +2
V — Vascular disease (MI, PAD, aortic plaque) +1
A — Age 65–74 +1
Sc — Sex category (female) +1

Total = sum of all applicable points (capped at 9)

The two double-weighted items share a logic: advanced age and a stroke that has already happened are the strongest signals in the set. Prior stroke in particular is the closest thing the score has to a settled predictor — the best guide to a future event is often a past one.

Published Annual Stroke Risk by Score

This calculator maps the computed score to the risk figures below, adapted from the widely-cited Friberg et al. 2012 Swedish registry validation cohort:

Approximate annual stroke risk by CHA²DS²-VASc score
Score	Approximate 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%

The figures are not perfectly monotonic — scores of 7, 8 and 9 were represented by small numbers of patients in the validation cohort, so those percentages carry wide uncertainty. This is registry data, not a smooth model, and the table is reproduced as published rather than tidied.

Why Age Appears Twice

Age is the only factor in the acronym occupying two separate letters, and this calculator handles it as a single graded band rather than two independent checks: 75 and over scores +2, 65 to 74 scores +1, and under 65 scores nothing. The scheme is stepped rather than continuous, which means a 74th birthday and a 75th birthday are separated by a full point — a reminder that the score is a clinical simplification of a smooth underlying relationship.

Note: This tool is presented as general reference for understanding how the score is constructed and what its published validation data showed. It is not a diagnosis, not personalised risk, and not a basis for any decision about anticoagulation — a decision that must weigh bleeding risk alongside stroke risk and belongs entirely with a cardiologist or physician who knows the full clinical picture.

Where the Score Appears

Atrial fibrillation guidelines — major cardiology societies reference it directly when framing anticoagulation discussion.
Shared decision-making — it gives patients and clinicians a common number to reason about together.
Risk communication research — the score is a standard example of how graded point systems translate multiple factors into one figure.

How to Use This Calculator

Enter Age (years) — the calculator assigns +2, +1 or +0 automatically from the bands above.
Select Sex; female adds +1 under the Sc criterion.
Tick each applicable checkbox: congestive heart failure, hypertension, diabetes, prior stroke or TIA, and vascular disease.
Select Calculate. The result shows the total score with a full line-by-line breakdown of which criteria contributed, plus the published risk figure for that score.

Related Calculations

For a different view of cardiovascular risk factors, see the Heart Attack Risk Calculator, or explore another point-based clinical scoring scheme with the Wells Score Calculator.

Principles of Stroke Risk Stratification: CHA₂DS₂-VASc

A CHA₂DS₂-VASc score calculator stratifies the annual risk of ischemic thromboembolic stroke in patients diagnosed with non-valvular Atrial Fibrillation (AFib). In clinical cardiology and electrophysiology, the CHA₂DS₂-VASc score serves as the definitive international guideline determining when to initiate oral anticoagulation therapy.

The CHA₂DS₂-VASc Clinical Scoring Criteria

Risk Factor Category	Clinical Definition	Assigned Points
C — Congestive Heart Failure	Left ventricular ejection fraction ≤ 40% or documented clinical CHF	+1 Point
H — Hypertension	Resting BP > 140/90 mmHg or active antihypertensive medication	+1 Point
A₂ — Age ≥ 75 Years	Patient age 75 or older	+2 Points (Major Risk)
D — Diabetes Mellitus	Fasting glucose > 126 mg/dL or active insulin / oral hypoglycemic Rx	+1 Point
S₂ — Stroke / TIA / Thromboembolism	Prior ischemic stroke, transient ischemic attack, or systemic embolus	+2 Points (Major Risk)
V — Vascular Disease	Prior myocardial infarction, peripheral artery disease (PAD), or aortic plaque	+1 Point
A — Age 65 to 74 Years	Patient age between 65 and 74	+1 Point
Sc — Sex Category (Female)	Female biological sex	+1 Point

Anticoagulation Treatment Recommendations (ACC / AHA / ESC Guidelines)

Score 0 (Men) / Score 1 (Women): Low risk (< 1.0%/year) — No Anticoagulation Recommended.
Score 1 (Men) / Score 2 (Women): Intermediate risk — Oral Anticoagulation should be considered.
Score ≥ 2 (Men) / Score ≥ 3 (Women): High risk — Direct Oral Anticoagulant (DOAC: Apixaban, Rivaroxaban, Dabigatran) Strongly Recommended!

Step-by-Step Worked Calculation Example

Example: Scoring a 72-Year-Old Female with AFib, Hypertension, and Diabetes

Problem: A 72-year-old woman with newly diagnosed atrial fibrillation has a medical history of hypertension and Type 2 diabetes. Calculate: (1) Total CHA₂DS₂-VASc score; (2) Estimated annual stroke risk; and (3) Clinical treatment directive.

Step 1: Tally Clinical Points:

Age 65-74 = +1 | Female Sex = +1 | Hypertension = +1 | Diabetes = +1

Total CHA₂DS₂-VASc Score = 1 + 1 + 1 + 1 = 4 Points

Step 2: Clinical Directive:

A score of 4 carries an estimated 4.0% to 5.0% annual stroke risk without treatment. Cardiology guidelines strongly direct starting a Direct Oral Anticoagulant (DOAC) such as Apixaban 5 mg BID, reducing stroke risk by over 65%.

Balancing Thromboembolic vs. Bleeding Risk (HAS-BLED Score)

Before initiating anticoagulation, cardiologists evaluate the patient's bleeding risk using the HAS-BLED Score (Hypertension, Abnormal Renal/Liver Function, Stroke History, Bleeding Predisposition, Labile INR, Elderly >65, Drugs/Alcohol):

A high HAS-BLED score (≥ 3) indicates elevated major hemorrhage risk, prompting closer clinical monitoring and blood pressure control rather than withholding lifesaving anticoagulation.

Cardioversion Anticoagulation Protocols

In patients undergoing electrical or pharmacological cardioversion for atrial fibrillation lasting > 48 hours, cardiology guidelines mandate at least 3 consecutive weeks of therapeutic anticoagulation prior to cardioversion and at least 4 weeks post-procedure.

Stroke Prevention in Atrial Fibrillation

Applying standardized CHA₂DS₂-VASc risk scoring ensures patients with atrial fibrillation receive guideline-directed anticoagulation to prevent catastrophic thromboembolic stroke.

Cardiovascular Risk Management

Combining anticoagulation therapy with rate or rhythm control optimizes cardiovascular outcomes in patients managing chronic atrial fibrillation.