CHA₂DS₂-VASc Calculator
What is CHA₂DS₂-VASc Calculator
The CHA₂DS₂-VASc score estimates the yearly risk of stroke in people with non-valvular atrial fibrillation and guides whether anticoagulation is warranted. It adds points for congestive heart failure, hypertension, age, diabetes, prior stroke, vascular disease and female sex, with age 75 or over and a prior stroke each worth two points. The total runs from 0 to 9.
How to use
- Enter the age in years, which scores 0, 1 or 2 points automatically.
- Select male or female.
- Tick each risk factor that applies: heart failure, hypertension, diabetes, prior stroke or TIA, and vascular disease.
- Read the score out of 9 and the estimated annual stroke risk.
When to use it
A patient with atrial fibrillation asks whether they need a blood thinner? Enter age 72, female, with hypertension and diabetes, and the score reaches 4 with an estimated annual stroke risk near 4.8 percent, well into the range where guidelines favour anticoagulation. It turns a list of risk factors into a single number you can discuss with the patient.
Frequently asked questions
What score means anticoagulation is recommended?
Guidelines generally recommend anticoagulation at a score of 2 or more in men and 3 or more in women, and consider it at 1 in men and 2 in women. A score of 0 in men or 1 in women (from sex alone) is low risk.
Why does female sex add a point?
Female sex is a risk modifier rather than a standalone risk factor: it raises stroke risk when other factors are present. That is why a score of 1 from sex alone is still considered low risk.
How is age scored?
Age is scored once and is mutually exclusive: 65 to 74 years adds 1 point, and 75 or over adds 2 points. Under 65 adds nothing. This tool derives the age points from the age you enter.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you enter values. Copy it from the address bar or use the Copy link button, and anyone who opens the link will see your exact inputs ready to go.
Related tools
A-a Gradient Calculator
Calculate the alveolar-arterial oxygen gradient from FiO2, PaO2 and PaCO2, and compare it to the expected value for age. Free and instant.
How Old Am I? Age Calculator
Find out exactly how old you are with this free age calculator. Enter your date of birth and get your age in years, months, days, zodiac sign, and more.
Anion Gap Calculator
Calculate the serum anion gap from sodium, chloride and bicarbonate, with optional potassium and albumin correction, to screen for metabolic acidosis.