CHA₂DS₂-VASc Score Calculator

Atrial fibrillation (AF) raises a person’s risk of stroke “by 3 to 5 times”, in the words of Singapore’s ACE Clinical Guideline on oral anticoagulation for AF (last updated 28 November 2023), which also records that about 19% of strokes in Singapore in 2020 occurred in patients with AF. Anticoagulants lower that risk and add a risk of bleeding; in a 2007 meta-analysis, warfarin reduced stroke by 64% compared with control (Hart et al., Ann Intern Med 2007). The CHA₂DS₂-VASc score, proposed by Lip and colleagues in Chest in 2010 using 1,084 patients from the Euro Heart Survey, estimates the stroke side of that trade-off from age, sex and five conditions.

How the score adds up

C, congestive heart failure, 1 point. H, hypertension, 1. A₂, age 75 or over, 2. D, diabetes, 1. S₂, prior stroke, TIA or thromboembolism, 2. V, vascular disease, 1. A, age 65–74, 1. Sc, female sex, 1. The maximum is 9. The percentage printed beside a score is the yearly rate of ischaemic stroke in one Swedish cohort of patients diagnosed between 2005 and 2008 and not taking anticoagulants, men and women counted together (Friberg et al., Eur Heart J 2012): 0.2% at a score of 0, 2.2% at 2, 7.2% at 5 and 12.2% at 9. It climbs steeply from 0 to 2, more slowly after, and dips at 8 (10.8%) below 7 (11.2%). Other cohorts report other figures for the same score. At a score of 2: 1.1% a year in Germany, 1.4% in the UK, 1.9% in the Netherlands and in Korea, and 2.2% in Sweden (Wicke et al., BMC Cardiovasc Disord 2019, Table 4). A percentage beside a score belongs to the cohort it came from, not to the person reading it.

CHA₂DS₂-VASc does not decide whether to anticoagulate. It estimates one side of a trade-off — the stroke risk — which a clinician then weighs against the bleeding risk the same patient carries.

The sex point, and what removing it did

On 30 August 2024 the European Society of Cardiology (ESC) replaced CHA₂DS₂-VASc with CHA₂DS₂-VA — the same score without the sex point, maximum 8 — and set one rule for everyone: anticoagulation recommended at 2 or more (class I) and to be considered at 1 (class IIa). The ESC 2020 rule it replaced read CHA₂DS₂-VASc at 2 or more in men and 3 or more in women for class I, and 1 in men and 2 in women for class IIa (both rules as tabulated by Boriani et al., Europace 2024, Table 1). The 2023 US guideline (ACC/AHA/ACCP/HRS) still reads CHA₂DS₂-VASc with those sex-specific cut-points, which it gives as examples of an estimated stroke risk of 2% a year or more (“anticoagulation is recommended”, class 1) and of 1% to under 2% (“anticoagulation is reasonable”, class 2a).

The two scores give a woman different numbers. They do not give her a different class. We ran all 192 combinations this page accepts — three age bands, two sexes and the five boxes ticked or not — through the kernel that produces the result. Dropping the sex point lowers each of the 96 female scores by exactly one and changes the class of none of the 192, under ESC 2020, ACC/AHA 2023, ESC 2024 and Singapore’s sex-free rule alike. The arithmetic explains it: a woman’s CHA₂DS₂-VASc is her CHA₂DS₂-VA plus one, and the women’s cut-points were already one higher. The 2024 ESC guideline says as much itself: because earlier guidelines gave women and men different score levels, CHA₂DS₂-VA “has effectively been in place”. The page still prints both scores, because the guidelines quote different ones.

The middle band, and the trial that tested it

The US guideline defines its middle band by risk, 1% to under 2% a year. The Swedish rates printed here fall outside that range at every middle-band score — 0.6% for a man at 1 and 2.2% for a woman at 2 — because they count men and women together by total score, while the guideline maps scores to risk sex by sex, and only by example. The result says so beside the number rather than hiding either figure. SINGLE-AF (Kim et al., N Engl J Med, published online 28 August 2026) enrolled 1,803 Korean patients in this band, “a score of 1 in men and 2 in women”, and compared a direct oral anticoagulant with no anticoagulation: the primary composite outcome occurred in 4 and 13 patients respectively over 24 months (hazard ratio 0.31). It is one trial in one country, with 23.7% women and a mean age of 60.

Newer anticoagulants against warfarin

In the trials pooled by Ruff et al. (Lancet 2014), the direct oral anticoagulants (apixaban, dabigatran, edoxaban and rivaroxaban) were each compared with warfarin. Together they showed fewer strokes or systemic emboli (relative risk 0.81) and less bleeding inside the skull (0.48), but more gastrointestinal bleeding (1.25). Which medicine suits whom is a clinical decision this page does not make.

Which score Asia uses

There is no single ASEAN rule. Singapore’s ACE Clinical Guideline has left sex out of its version of CHA₂DS₂-VASc since its first edition of 20 November 2017, seven years before ESC renamed the score; the current edition (28 November 2023) says “gender does not contribute to the decision”, counts hypertrophic cardiomyopathy under heart failure and, for a score of 1, lists age and comorbidity groups at higher risk. Thailand’s 2025 guideline recommends CHA₂DS₂-VA “for the Thai population due to its simplicity”. The Asia Pacific Heart Rhythm Society’s 2021 focused update keeps sex-specific thresholds: 2 or more in men, 3 or more in women. The 2023 US guideline also lists a different modification, the Taiwanese age-50 version (Chao et al., Stroke 2016), which keeps the sex point and gives a point from age 50 to 74; it is “validated in Asian cohort”, and this page does not compute it. The 2024 ESC guideline lists ethnicity, Asian included, among the “other markers that modify an individual’s risk”.