HAS-BLED Bleeding Risk Calculator for Atrial Fibrillation
Calculate the original HAS-BLED 0–9 bleeding-risk-factor score for adults with established atrial fibrillation, with exact criteria and current guideline limits.
Content updated: View sources
QuickMedCalc is developed and maintained by an independent developer. Medical content is not independently reviewed by a physician.
Formula and medical content are based on the references listed on this page. See sources, About, and Sources and Review Process.
Model identity: this page reproduces the original 2010 nine-point HAS-BLED score after every input is explicitly entered. It does not diagnose atrial fibrillation, measure bleeding risk directly, or decide whether anticoagulation should be started, stopped, withheld, selected, or dosed.
About
This HAS-BLED bleeding risk calculator reproduces the original 2010 nine-item point score for adults with clinician-established atrial fibrillation. It reports a structured count of submitted bleeding-risk factors and a complete criterion audit; it does not diagnose AF or active bleeding. [1]
Current U.S. and ESC guidance does not support using a bleeding score by itself to decide whether oral anticoagulation should be started, stopped, or withheld. NICE uses the separate ORBIT score for absolute bleeding-risk assessment in its UK AF pathway. This page calculates neither an individual annual probability nor a treatment recommendation.[3, 4, 5]
Formula
Interpretation
The nine HAS-BLED criteria and exact boundaries
| Letter | Original item | Definition | Points | Boundary |
|---|---|---|---|---|
| H | Hypertension | Uncontrolled hypertension, defined as systolic BP >160 mmHg | 1 | Exactly 160 mmHg scores 0; this page does not diagnose hypertension. |
| A | Abnormal renal function | Chronic dialysis, kidney transplantation, or serum creatinine ≥200 µmol/L (about 2.26 mg/dL) | 1 | No eGFR or creatinine-clearance substitution; renal can score separately from liver. |
| A | Abnormal liver function | Chronic hepatic disease, or bilirubin >2× ULN together with AST, ALT, or alkaline phosphatase >3× ULN | 1 | The page does not infer liver disease from one symptom or laboratory value. |
| S | Stroke history | Previous stroke in the applicable clinical history | 1 | Not a new stroke, TIA, or embolic-event diagnosis. |
| B | Bleeding history or predisposition | Prior major bleeding or a bleeding diathesis, such as anemia in the original definition | 1 | No hemoglobin-based diagnosis or active-bleeding assessment. |
| L | Labile INR | Unstable/high INR control or time in therapeutic range below 60% (TTR <60%) | 1 | VKA-only concept; stable VKA/TTR ≥60% and non-VKA status score 0. |
| E | Elderly | Age >65 completed years | 1 | The strict >65-year boundary applies; exactly 65 completed years scores 0 and age 66 scores 1. |
| D | Drugs | Concomitant antiplatelet agent or NSAID | 1 | A separate point from alcohol; no medicine or dose recommendation. |
| A | Alcohol | Alcohol intake ≥8 units/week | 1 | A separate point from drugs; units are not converted across countries. |
Each original criterion contributes one point, for a total range of 0–9.
- Letter
- H
- Original item
- Hypertension
- Definition
- Uncontrolled hypertension, defined as systolic BP >160 mmHg
- Points
- 1
- Boundary
- Exactly 160 mmHg scores 0; this page does not diagnose hypertension.
- Letter
- A
- Original item
- Abnormal renal function
- Definition
- Chronic dialysis, kidney transplantation, or serum creatinine ≥200 µmol/L (about 2.26 mg/dL)
- Points
- 1
- Boundary
- No eGFR or creatinine-clearance substitution; renal can score separately from liver.
- Letter
- A
- Original item
- Abnormal liver function
- Definition
- Chronic hepatic disease, or bilirubin >2× ULN together with AST, ALT, or alkaline phosphatase >3× ULN
- Points
- 1
- Boundary
- The page does not infer liver disease from one symptom or laboratory value.
- Letter
- S
- Original item
- Stroke history
- Definition
- Previous stroke in the applicable clinical history
- Points
- 1
- Boundary
- Not a new stroke, TIA, or embolic-event diagnosis.
- Letter
- B
- Original item
- Bleeding history or predisposition
- Definition
- Prior major bleeding or a bleeding diathesis, such as anemia in the original definition
- Points
- 1
- Boundary
- No hemoglobin-based diagnosis or active-bleeding assessment.
- Letter
- L
- Original item
- Labile INR
- Definition
- Unstable/high INR control or time in therapeutic range below 60% (TTR <60%)
- Points
- 1
- Boundary
- VKA-only concept; stable VKA/TTR ≥60% and non-VKA status score 0.
- Letter
- E
- Original item
- Elderly
- Definition
- Age >65 completed years
- Points
- 1
- Boundary
- The strict >65-year boundary applies; exactly 65 completed years scores 0 and age 66 scores 1.
- Letter
- D
- Original item
- Drugs
- Definition
- Concomitant antiplatelet agent or NSAID
- Points
- 1
- Boundary
- A separate point from alcohol; no medicine or dose recommendation.
- Letter
- A
- Original item
- Alcohol
- Definition
- Alcohol intake ≥8 units/week
- Points
- 1
- Boundary
- A separate point from drugs; units are not converted across countries.
The two A items can contribute two points together, and the two drugs/alcohol items can contribute two points together. Technical age and SBP input limits are safety boundaries, not healthy ranges.[1]
How to interpret HAS-BLED under current guidance
HAS-BLED is useful as a structured review of documented bleeding-risk factors. The 2023 ACC/AHA/ACCP/HRS guideline notes that common bleeding scores have limited discrimination and overlap with stroke-risk factors; they cannot be interpreted in isolation or determine oral- anticoagulation eligibility. The 2024 ESC guideline likewise says bleeding-risk scores should not decide whether anticoagulants are started or withdrawn. [3, 4]
Older HAS-BLED literature commonly used a total of 3 or more as a prompt for closer review. This page does not turn that historical, source-specific context into a dynamic category, individual event probability, contraindication, or treatment cutoff. The original and external-validation cohorts remain model provenance rather than a score-to-probability lookup. [1, 2]
What HAS-BLED calculates
The form requires an established-AF context, completed age, actual systolic blood pressure, six explicit Yes/No responses, and a specific VKA/INR-control state. It reports the original 0–9 total, names the positive criteria, and shows the complete submitted audit. It does not infer missing criteria, read a medical record, or expand the model to VTE populations. [1]
Modifiable and non-modifiable bleeding factors
The useful next step is factor review, not an automatic treatment action. Potentially modifiable or manageable factors may include uncontrolled blood pressure, poor VKA INR control, concomitant antiplatelet/NSAID use, and alcohol exposure. Age, previous stroke, previous major bleeding, and chronic organ disease are not made modifiable by changing this form. Reassessment matters because clinical context and exposures can change. [3, 4, 5]
INR means international normalized ratio, TTR means time in therapeutic range, VKA means vitamin K antagonist, and NSAID means nonsteroidal anti-inflammatory drug. Direct oral anticoagulants do not use INR to titrate anticoagulation; selecting non-VKA therefore adds no labile-INR point without implying that DOAC therapy has no bleeding risk.[1, 3]
HAS-BLED vs CHA₂DS₂-VASc
HAS-BLED organizes bleeding-risk factors; CHA₂DS₂-VASc is a separate historical stroke and systemic-embolism risk-factor score in AF. They answer different questions, their totals must not be subtracted, and this page does not calculate stroke risk or net clinical benefit. Use the separate CHA₂DS₂-VASc calculator for that score.[1, 3]
HAS-BLED vs ORBIT and the NICE pathway
ORBIT is a different bleeding-risk model with different inputs. NICE currently prefers ORBIT for absolute bleeding-risk assessment in its UK AF pathway because its evidence review found better calibration for that purpose. This does not invalidate HAS-BLED, apply universally outside the NICE pathway, or permit mathematical conversion between the scores. This page does not calculate ORBIT.[5, 6]
Important limitations
HAS-BLED does not establish active bleeding, diagnose hypertension or organ disease, select warfarin versus a DOAC, choose a medicine or dose, set an INR target or monitoring interval, or decide whether oral anticoagulation should be started, stopped, continued, or withheld. It does not fully capture current hemoglobin, platelet disorders, cancer, falls or frailty, pregnancy, recent procedures or trauma, changing organ function, adherence, patient preferences, or every interaction.[3, 4]
References
- Pisters R, Lane DA, Nieuwlaat R, de Vos CB, Crijns HJGM, Lip GYH. A novel user-friendly score (HAS-BLED) to assess 1-year risk of major bleeding in patients with atrial fibrillation: the Euro Heart Survey. Chest. 2010;138(5):1093–1100. PMID 20299623. DOI 10.1378/chest.10-0134.
- Lip GYH, Frison L, Halperin JL, Lane DA. Comparative validation of a novel risk score for predicting bleeding risk in anticoagulated patients with atrial fibrillation: the HAS-BLED score. J Am Coll Cardiol. 2011;57(2):173–180. PMID 21111555. DOI 10.1016/j.jacc.2010.09.024.
- Joglar JA, Chung MK, Armbruster AL, et al. 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation. Circulation. 2024;149(1):e1–e156. PMID 38033089. DOI 10.1161/CIR.0000000000001193.
- Van Gelder IC, Rienstra M, Bunting KV, et al. 2024 ESC Guidelines for the management of atrial fibrillation developed in collaboration with EACTS. Eur Heart J. 2024;45(36):3314–3414. PMID 39210723. DOI 10.1093/eurheartj/ehae176.
- National Institute for Health and Care Excellence. Atrial fibrillation: diagnosis and management. NICE guideline NG196. Recommendations on assessing stroke and bleeding risks. Published 2021; updated 2021.
- O’Brien EC, Simon DN, Thomas LE, et al. The ORBIT bleeding score: a simple bedside score to assess bleeding risk in atrial fibrillation. Eur Heart J. 2015;36(46):3258–3264. PMID 26424865. DOI 10.1093/eurheartj/ehv476.
FAQ
It reproduces the original 2010 nine-item HAS-BLED point total, from 0 to 9, for an adult with clinician-established atrial fibrillation. It reports a structured bleeding-risk-factor count and submitted criterion audit; it does not diagnose AF or bleeding, calculate a universal individual probability, or decide anticoagulation treatment.
One point each is assigned for uncontrolled systolic blood pressure above 160 mmHg, abnormal renal function, abnormal liver function, previous stroke, prior major bleeding or bleeding predisposition, labile INR on a vitamin K antagonist, age above 65, concomitant antiplatelet or NSAID use, and alcohol intake of at least 8 units per week. Renal and liver function score separately, as do drugs and alcohol, for a total range of 0–9.
Sources: [1]
It is the number of original HAS-BLED risk-factor points present in the submitted assessment. Older literature commonly used 3 or more as a prompt for closer review, but this page does not apply a dynamic risk category, individual event probability, contraindication, or treatment cutoff. Current U.S. and ESC guidance says bleeding scores must not be used alone to decide oral-anticoagulation eligibility or withdrawal.
No. The original model uses a strict age above 65 boundary. A person aged exactly 65 completed years scores zero for this item; age 66 scores one. Later summaries may use different symbols, but this page preserves the source model.
Sources: [1]
The original labile-INR point applies to a patient receiving a vitamin K antagonist when INR control is unstable or high, or time in therapeutic range is below 60%. Not receiving a vitamin K antagonist adds zero for this item. Direct oral anticoagulants do not use INR to titrate anticoagulation, so this item does not measure DOAC adherence, exposure, dose suitability, or bleeding risk.
HAS-BLED organizes bleeding-risk factors. CHA₂DS₂-VASc is a separate historical stroke and systemic-embolism risk-factor score in atrial fibrillation. They answer different questions, their totals must not be subtracted into a net score, and this page does not calculate stroke risk or net clinical benefit.
ORBIT is a separate bleeding-risk model with different inputs. NICE currently prefers ORBIT for absolute bleeding-risk assessment in its UK AF pathway because its evidence review found better calibration for that purpose. This does not make HAS-BLED invalid or ORBIT universally preferred, and one score cannot be converted into the other.
No. Current U.S. and ESC guidance does not support using a bleeding-risk score in isolation to determine oral-anticoagulation eligibility or withdrawal. This calculator does not establish an indication or contraindication, choose warfarin or a DOAC, recommend a medicine or dose, set monitoring, or instruct someone to start, stop, continue, or withhold treatment.
Related Calculators
CHA₂DS₂-VASc
Calculate the classic 2010 CHA₂DS₂-VASc risk-factor point total for adults with clinician-established atrial fibrillation or atrial flutter.
GRACE
Estimate GRACE 2.0 in-hospital and one-year ACS risk from the standard eight inputs, with the historical Classic GRACE 1.0 point score retained separately.
RCRI
Calculate the original six-item Lee RCRI point score and class for adult preoperative assessment before noncardiac surgery, with source-specific limitations.
Disclaimer
Educational and informational reference only. Not intended to replace professional medical advice, diagnosis, treatment, or independent verification.