HAS-BLED Calculator
Bleeding risk on anticoagulation.
About this tool
HAS-BLED estimates the 1-year risk of major bleeding for people on oral anticoagulation for atrial fibrillation. It's used to identify modifiable risk factors — not to decide against anticoagulation in patients who need it.
A high HAS-BLED score should prompt closer follow-up and correction of modifiable factors (BP, alcohol, NSAID/antiplatelet use, INR stability), not withdrawal of anticoagulation.
Source: Pisters R et al., Chest 2010.
Frequently asked questions
Should a high HAS-BLED score stop anticoagulation?
No. Guidelines specifically warn against this. A high score is a checklist of fixable risks — and in most AFib patients, the stroke prevention benefit still outweighs bleeding risk.
Which factors are modifiable?
Blood pressure control, INR stability (if on warfarin), avoiding concomitant antiplatelets/NSAIDs, and reducing alcohol intake.
⚕️ Educational only — not a substitute for professional medical advice, diagnosis, or treatment. In an emergency call your local emergency services.