CHA₂DS₂-VASc score calculator for stroke risk in atrial fibrillation
For healthcare professionals and students. Check results against your local protocols and clinical judgement; this tool does not give medical advice.
This CHA₂DS₂-VASc calculator (often searched as “chads vasc” or “chads vasc 2 score”) adds up the stroke and thromboembolism risk factors in a patient with atrial fibrillation. Enter the age, tick the conditions that apply and choose the sex, and it shows the CHA₂DS₂-VASc score out of 9 with each criterion listed, together with two related scores: CHA₂DS₂-VA, the sex-neutral version adopted by the 2024 European Society of Cardiology guidelines, and the older CHADS₂.
It is meant for students learning the score, and for clinicians who want the working laid out before they apply their own guideline. It does not recommend treatment. Nothing you enter leaves your browser.
How to use the CHA2DS2-VASc Score Calculator
- Type the age in years — the tool scores 65–74 as 1 point and 75 or over as 2.
- Choose the sex.
- Tick each condition that applies: heart failure or LV dysfunction, hypertension, diabetes, prior stroke/TIA/thromboembolism, vascular disease.
- Read the CHA₂DS₂-VASc score and the itemised points, then compare CHA₂DS₂-VA and CHADS₂ in the boxes below it.
- Use Copy result to paste the score and its components into your notes.
CHA2DS2-VASc Score Calculator features
Three scores at once
CHA₂DS₂-VASc, the ESC 2024 CHA₂DS₂-VA (without the sex point) and CHADS₂, from the same answers.
Age scored from the number
Type the age; the 65–74 and 75-plus points are applied automatically, so they cannot both be ticked by mistake.
Itemised breakdown
Every letter of the acronym is listed with the patient’s value and the points it adds.
Context notes
Flags a score made up of female sex alone, use outside adults, and valvular AF that the score was not designed for.
Copyable summary
One line with all three scores and the risk factors present, ready for a clinic letter or handover.
CHA₂DS₂-VASc points table
The score was published by Lip GYH, Nieuwlaat R, Pisters R, Lane DA and Crijns HJGM in Chest 2010;137(2):263–272, refining the 2006 Birmingham/NICE schema and testing it in 1,084 patients from the Euro Heart Survey on atrial fibrillation. Thromboembolism rates rose with increasing score, and patients classified as low risk had no thromboembolic events in that cohort. The maximum is 9, because the two age items cannot both apply.
| Letter | Risk factor | Points |
|---|---|---|
| C | Congestive heart failure or left ventricular dysfunction | 1 |
| H | Hypertension | 1 |
| A₂ | Age 75 years or over | 2 |
| D | Diabetes mellitus | 1 |
| S₂ | Prior stroke, transient ischaemic attack or thromboembolism | 2 |
| V | Vascular disease (prior myocardial infarction, peripheral artery disease, aortic plaque) | 1 |
| A | Age 65–74 years | 1 |
| Sc | Sex category: female | 1 |
CHA₂DS₂-VASc, CHA₂DS₂-VA and CHADS₂ compared
CHADS₂ (Gage BF et al., JAMA 2001;285(22):2864–2870) scores heart failure, hypertension, age 75 or over and diabetes at 1 point each and prior stroke/TIA at 2, out of 6. CHA₂DS₂-VASc added vascular disease, the 65–74 age band and female sex, and doubled the weight of age 75 or over, so fewer patients fall into an uncertain middle group.
The 2024 ESC guidelines for atrial fibrillation (Van Gelder IC et al., Eur Heart J 2024;45(36):3314–3414) replaced CHA₂DS₂-VASc with CHA₂DS₂-VA, which is the same score without the sex point, because including sex “complicates clinical practice both for healthcare professionals and patients”. Coverage of the guideline quotes it as recommending oral anticoagulation at a CHA₂DS₂-VA of 2 or more and considering it at 1, with shared decision-making.
The 2023 ACC/AHA/ACCP/HRS guideline (Joglar JA et al., Circulation 2024;149(1)) endorses a validated risk score such as CHA₂DS₂-VASc and bases stroke-prevention therapy on the estimated annual thromboembolic risk (2% or more per year), weighed against bleeding risk. Read the guideline you work under rather than a single threshold here; guideline summaries checked 19 October 2026.
Limits of the score
- It was derived and validated in adults with non-valvular AF. Patients with moderate-to-severe mitral stenosis or mechanical valves are handled separately in guidelines.
- Its discrimination is modest: the original paper reported a C-statistic of about 0.6 in the Euro Heart Survey cohort. Event rates per point differ between cohorts and should be taken from your guideline.
- It does not measure bleeding risk, which guidelines assess separately with modifiable bleeding risk factors.
- Risk factors change: a patient who develops hypertension or turns 65 needs the score recalculated.
CHA2DS2-VASc Score Calculator FAQ
How is the CHA₂DS₂-VASc score calculated?
One point each for heart failure, hypertension, diabetes, vascular disease, age 65–74 and female sex; two points each for age 75 or over and for prior stroke, TIA or thromboembolism. The CHA₂DS₂-VASc calculator above adds them for you, up to 9.
Is “chads vasc 2” the same as CHA₂DS₂-VASc?
Yes. The subscript 2s mean that age 75 or over and prior stroke score two points each; people often type it as “chads vasc 2”.
What is CHA₂DS₂-VA?
The score without the female-sex point, used by the 2024 ESC atrial fibrillation guidelines. It runs from 0 to 8 and is shown alongside CHA₂DS₂-VASc here.
Does female sex alone count as a risk factor?
It adds a point to CHA₂DS₂-VASc, but in the absence of other risk factors it is generally regarded as a risk modifier rather than a reason to treat, which is one reason the ESC removed it in 2024.
What score needs anticoagulation?
That decision belongs to the guideline and the clinician, weighing bleeding risk and the patient’s preferences. The ESC 2024 and ACC/AHA 2023 guidelines set their own thresholds; this tool reports the score only.
Can I use it for atrial flutter or for a patient with a mechanical valve?
Guidelines generally apply the same stroke-risk approach to atrial flutter, but mechanical valves and moderate-to-severe mitral stenosis are outside the score. For suspected venous clots, use the Wells score calculator instead.