HAS-BLED Score Calculator (Bleeding Risk on Anticoagulation)
The HAS-BLED score estimates one-year risk of major bleeding in patients with atrial fibrillation on oral anticoagulation. It uses nine binary components: hypertension (uncontrolled), abnormal renal function, abnormal liver function, prior stroke, bleeding history or predisposition, labile INR, age over 65, drugs (antiplatelet or NSAID), and excessive alcohol. The score ranges 0–9. The ACC/AHA/HRS 2019 atrial fibrillation update references HAS-BLED as one of several bleeding-risk frameworks to be weighed alongside CHA₂DS₂-VASc when deciding whether to start or continue anticoagulation.
This tool is for educational and decision-support use only. It does not replace independent clinical judgement. Always verify against the current guideline, FDA label, or specialty reference cited below before acting. Do not enter patient identifiers (name, MRN, dates of service).
Tool
Who this is for
- Hospitalists weighing benefits vs bleeding risk before initiating DOACs
- Internal medicine residents on AF anticoagulation decisions
- Cardiology and primary care providers managing chronic AF
How to interpret the result
| Score / band | Interpretation |
|---|---|
| 0–1 | Low — major-bleeding risk is generally low; HAS-BLED rarely overrides anticoagulation. |
| 2 | Moderate — closer monitoring and modifiable-factor optimisation are commonly considered. |
| ≥ 3 | High — modifiable risk factors (BP, INR variability, NSAIDs, alcohol) should be addressed; HAS-BLED is not by itself a reason to withhold anticoagulation. |