CHA₂DS₂-VASc is the score doctors use to estimate stroke risk in people with atrial fibrillation (AF) — the irregular heart rhythm that lets clots form in the heart and travel to the brain. This page works out the score from the same factors a cardiologist uses, and turns the number into a plain one-in-N chance per year.

It is for people who have been told they have AF and want to understand the number behind a blood-thinner conversation. Each letter stands for a risk factor — heart failure, high blood pressure, age, diabetes, prior stroke, vascular disease and sex — and they add up to a score that maps to an annual stroke risk.

It runs privately in your browser. The point is not to decide anything alone, but to walk into the cardiology or GP conversation already understanding what the score means and why it matters.

General information to help you prepare for your GP — not a diagnosis, not personal medical advice.

Dr HB LoIntegrative GP CHA₂DS₂-VA · AF stroke-risk prep

CHA₂DS₂-VA / CHA₂DS₂-VASc score

What your AF stroke-risk number actually means.

Your doctor gave you a CHADS-VASc score and you walked out not quite sure what it meant. Tick the same boxes here and we'll turn it into a plain "1 in this many people" — so you can have the blood-thinner conversation as a participant, not a passenger.

Nothing you tick leaves your browser. This runs entirely on your device.

Australian score · CHA₂DS₂-VA — the score Australian heart guidelines use
International · CHA₂DS₂-VASc — adds a point for being female
Tick what applies — the score tallies as you go
0 / +1 / +2
This is the one box we need to show you a number.
If a doctor has ever told you your blood pressure is high, or you take tablets for it, tick yes. Not sure? Leave it and ask your GP — your tool will note it.
Ticking this for something happening now? If you have stroke signs right now (face drooping, arm weakness, slurred speech), call 000 — don't keep filling this in.
+1 / 0
The Australian score (CHA₂DS₂-VA) needs no sex answer — you get a full, valid result without telling us. This score was validated on sex recorded at birth; it's a rough population tool, not a personal verdict — your GP individualises it.

Or tap an example to fill it in

This tool helps you prepare — it can't tell if something is serious. If you're worried it might be urgent, call 000 or your GP now.

What your score means

have a stroke this year (filled, clustered top-left) do not (outline only)

The honest part

    Three questions to ask your GP about blood-thinners

    1. With my score, do Australian guidelines suggest we discuss a blood-thinner — and is now the time?

    2. What's my bleeding risk on a blood-thinner, and how does it weigh against my stroke risk?

    3. If we don't start one, what would change your mind — and when should we review this?

    Take it with you

    Email this one-pager to take to your appointment

    Your score, what it means in plain numbers, and the three questions to ask about blood-thinners — on one page you can hand to your GP.

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    Deciding whether to actually start a blood-thinner? The full AF stroke-prevention kit walks you through both sides — stroke risk and bleeding risk side by side, warfarin vs the newer tablets, and the exact questions to bring. See the bleeding-risk tool (HAS-BLED) and the AF anticoagulation question card.

    via drhblo.com/tools · general information, not personal medical advice

    Sources

    Stroke-risk figures and AU CHA₂DS₂-VA thresholds verified 2026-06-09 via WebSearch against AU primary sources (CSANZ/NHFA 2018 guideline, Australian Prescriber, MJA). Lip-2010 percentages are the historical validation set; contemporary AU cohorts run lower — caveat shown in the honesty panel.

    How to read your result

    The score runs from 0 upward. As a rough guide, a score of 0 (men) carries a very low annual stroke risk, while higher scores climb steeply — by a score of 4 the annual risk is in the order of several per cent per year, and it keeps rising from there. The exact figures sit in the AF guideline tables, and the tool shows the band your score falls into.

    Australia increasingly uses CHA₂DS₂-VA — the same score with the sex (female) point removed — because sex alone is no longer counted as an independent risk factor. That means your Australian score may be one point lower than an older overseas calculator would give. The tool explains where your points come from so the difference makes sense.

    A score is a starting point for a decision, not the decision itself. It estimates stroke risk; it does not weigh that against bleeding risk, which is a separate calculation (HAS-BLED). The two are read together, with your doctor, to decide whether a blood thinner is the right call for you.

    Australian guideline context

    The National Heart Foundation of Australia and the Cardiac Society of Australia and New Zealand (CSANZ) jointly publish the Australian Clinical Guidelines for the Diagnosis and Management of Atrial Fibrillation, which set out how CHA₂DS₂-VA is used in Australian practice and when anticoagulation is recommended.

    Under that guideline, a blood thinner is generally considered once the score reaches a defined threshold, balanced against bleeding risk — and the choice between a direct oral anticoagulant (DOAC) and warfarin is itself a guideline-led conversation. healthdirect's AF page is a plain-language starting point for patients.

    What to do with the result

    Take your score to your GP or cardiologist and ask how it sits against your bleeding risk: "My CHA₂DS₂-VA score is X — what does that mean for whether I need a blood thinner, and how does my bleeding risk weigh against it?" That question pairs the two halves of the decision.

    A high score is a reason to discuss protection from stroke, not a reason to start or stop any medicine on your own. The specific drug, dose and timing are always your doctor's call, with both scores in front of them.

    Common questions

    Why is my Australian score lower than an online calculator I found?
    Many overseas calculators still add a point for being female (the full CHA₂DS₂-VASc). Australian practice has largely moved to CHA₂DS₂-VA, which drops that point because sex alone is not treated as an independent stroke risk factor. So an Australian score is often one lower.
    Does a high score mean I will definitely have a stroke?
    No. The score estimates the chance of a stroke per year for people with your risk profile. It is a probability used to guide decisions about stroke prevention — not a prediction about you specifically.
    Is this the same as my bleeding risk?
    No — bleeding risk is a separate score (HAS-BLED). CHA₂DS₂-VA estimates stroke risk; the two are weighed together with your doctor to decide about anticoagulation.

    Related on this site

    Sources

    General information to help you prepare for your GP — not a diagnosis, not personal medical advice. This tool does not start, stop or change any medicine. If something is urgent, call 000.

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