HAS-BLED Bleeding Risk Calculator
Calculate the original 2010 HAS-BLED 0–9 bleeding-risk-factor score for adults with established atrial fibrillation.
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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 page reproduces the original 2010 HAS-BLED nine-item point score for an adult with clinician-established atrial fibrillation. The Euro Heart Survey included ECG- or Holter-documented AF across oral-anticoagulant, antiplatelet-only, and no-antithrombotic groups; the page does not read an ECG, watch, pulse, or symptom report. [1]
The score is a historical risk-factor count, not a direct measurement, AF screen, bleeding diagnosis, stroke-risk score, anticoagulation net- benefit calculation, or universal individual one-year probability. It does not select, start, stop, withhold, or dose VKA, DOAC, antiplatelet, or NSAID therapy. [3, 7]
Current guidance separates bleeding-factor review from the decision to use oral anticoagulation: ACC/AHA/ACCP/HRS describes the limited discrimination of common scores, ESC emphasizes repeat management of modifiable factors, and NICE prioritizes ORBIT in its UK pathway. Those are source-specific frameworks, not a replacement algorithm embedded in this calculator. [3, 7, 9, 10]
Formula
Interpretation
Original nine-item definition and strict boundaries
| Letter | Original item | Definition | Points | This page does not do |
|---|---|---|---|---|
| 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. |
The two A items can contribute two points together, and the two D items can contribute two points together; they are not merged. The technical age and SBP input limits are safety boundaries, not healthy ranges or diagnostic thresholds. [1]
Original Euro Heart Survey observations
| Score | Complete-score participants | Major bleeds | Bleeds per 100 patient-years |
|---|---|---|---|
| 0 | 798 | 9 | 1.13 |
| 1 | 1,286 | 13 | 1.02 |
| 2 | 744 | 14 | 1.88 |
| 3 | 187 | 7 | 3.74 |
| 4 | 46 | 4 | 8.70 |
| 5 | 8 | 1 | 12.50 |
| 6 | 2 | 0 | 0.0 |
| 7–9 | 0 | — | Not observed |
Pisters reported 3,978 adults with complete one-year follow-up and 53 major bleeding events in that cohort. The complete-score event table is a smaller analysis with only 48 major bleeds among 3,071 people; score 0 and 1 are not monotonic, scores 4–6 are sparse, and scores 7–9 were not observed. These historical rates must not be used as modern DOAC-era personal probabilities. This page does not convert one submitted total into a universal personal probability. [1]
In that source-specific study, major bleeding was a clinically consequential bleeding event such as bleeding requiring hospitalization, a hemoglobin fall of at least 2 g/dL, or transfusion of at least 2 units. This historical outcome definition is not an active-bleeding diagnosis or a rule for this calculator to infer from one submitted field. [1]
Lip provided external validation in anticoagulated AF, while a later systematic review found variable calibration and no basis for a precise patient-level lookup. The studies are not combined into a new score.[2, 12]
Current guideline pathways and modifiable factors
The 2023 U.S. AF guideline recommends identifying specific bleeding factors and notes that common scores have limited discrimination and overlapping stroke factors. A score cannot be interpreted in isolation and cannot alone determine OAC eligibility or net clinical benefit. The 2024 ESC guideline does not endorse one score for every patient and says bleeding factors should be revisited and managed; a bleeding score should not decide whether anticoagulation is started or withdrawn, and few factors are reasons by themselves to withdraw OAC.[3, 7, 8]
Potentially modifiable or manageable issues include uncontrolled blood pressure, poor VKA INR control, concomitant antiplatelet/NSAID use, harmful alcohol use, and reversible anemia. Age, prior stroke, prior major bleeding, and some chronic organ disease are not made modifiable by changing this form. The page identifies submitted factors but does not prescribe an intervention. [8, 9]
NICE recommends ORBIT for absolute bleeding-risk assessment in its UK pathway because of its comparative calibration. ORBIT, ABC-bleeding, ATRIA, and HEMORR₂HAGES use different variables; this page calculates none of them. [9, 10, 11]
VKA, DOAC, and follow-up boundaries
INR and TTR are vitamin K antagonist management concepts. Direct oral anticoagulants do not use INR monitoring to titrate anticoagulation; the non-VKA option therefore scores zero for this original labile-INR item, without implying that DOACs have no bleeding risk. HAS-BLED does not assess DOAC dose suitability, adherence, all interactions, body weight, or every kidney-function detail. [1, 3]
INR means international normalized ratio; TTR means time in therapeutic range; VKA means vitamin K antagonist; and NSAID means nonsteroidal anti-inflammatory drug.
Blood pressure, organ function, medicines, alcohol, INR control, and bleeding history can change. A score is a submission-time audit, not a trend or a causal estimate of an intervention. Important omitted or incompletely represented factors include active bleeding, current hemoglobin, platelet disorders, cancer, falls or frailty, pregnancy, recent procedure or trauma, changing organ function, acute illness, adherence, and patient preferences. [3, 8]
HAS-BLED does not fully represent anemia severity, platelet disorders, falls, cancer, frailty, kidney or liver trajectory, drug interactions, adherence, or patient preferences.
Some older publications used HAS-BLED ≥3 as a prompt to review factors, but that historical phrase is not connected to this result, is not a universal cutoff, and is not a reason here to start, stop, reject, select, or adjust anticoagulation. HAS-BLED also cannot be subtracted from CHA₂DS₂-VASc to create a net score. [1, 3, 7]
Online guideline corrections checked
The current online ACC/AHA/ACCP/HRS guideline was checked together with its three formal corrections. They are preserved as separate sources so the bleeding-risk limitations above remain traceable to the corrected publication record; none changes this page’s original 2010 arithmetic.[3, 4, 5, 6]
What this calculator does and does not read
The form accepts an assessment context, completed age, systolic blood pressure, six yes/no criterion states, and a VKA/INR-control state. It does not read ECGs, pulse data, symptoms, laboratory values, medication names or doses, alcohol history beyond the selected original item, or a medical record. Every field must be explicitly entered, and editing a field clears the old result.
How to read a submitted total
The neutral result cards show only the original point total and how many criteria were present. They do not show a low, moderate, or high label, an event probability, or an anticoagulation instruction. The static table above is retained for source-specific historical context, not for a score-to-probability lookup.
Why the total needs clinical context
A score can identify a documented factor for review, but it cannot establish active bleeding, diagnose hypertension, kidney or liver disease, determine stroke risk, or quantify net clinical benefit. The appropriate pathway remains dependent on the person, treatment, time, competing risks, and current guidance.
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.
- Correction to: 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation. Circulation. 2024;149(1):e167. DOI 10.1161/CIR.0000000000001207.
- Correction to: 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation. Circulation. 2024;149(9):e936. DOI 10.1161/CIR.0000000000001218.
- Correction to: 2023 ACC/AHA/ACCP/HRS Guideline for the Diagnosis and Management of Atrial Fibrillation. Circulation. 2024;149(24):e1413. DOI 10.1161/CIR.0000000000001263.
- 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.
- Gorog DA, Gue YX, Chao TF, et al. Assessment and mitigation of bleeding risk in atrial fibrillation and venous thromboembolism: a position paper from the ESC Working Group on Thrombosis. Europace. 2022;24(11):1844–1871. PMID 35323922. DOI 10.1093/europace/euac020.
- 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.
- Hijazi Z, Oldgren J, Lindbäck J, et al. The novel biomarker-based ABC-bleeding risk score for patients with atrial fibrillation: a derivation and validation study. Lancet. 2016;387(10035):2302–2311. PMID 27056738. DOI 10.1016/S0140-6736(16)00741-8.
- Zhu W, He W, Guo L, Wang X, Hong K. The HAS-BLED score for predicting major bleeding risk in anticoagulated patients with atrial fibrillation: a systematic review and meta-analysis. Clin Cardiol. 2015;38(9):555–561. PMID 26418409. DOI 10.1002/clc.22435.
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 historical risk-factor count and submitted criterion audit; it does not screen for or diagnose AF, diagnose bleeding, calculate a universal individual probability, or calculate stroke risk or net clinical benefit. It cannot assess net clinical benefit by itself or make an anticoagulation decision.
It is for an adult whose atrial fibrillation has already been established by the applicable clinical assessment. The original Euro Heart Survey included adults with ECG- or Holter-documented AF across oral-anticoagulant, antiplatelet-only, and no-antithrombotic groups; this page does not read an ECG, watch, pulse, or symptom report and cannot screen for, diagnose, or exclude AF.
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]
The original criterion is uncontrolled systolic blood pressure strictly above 160 mmHg. Exactly 160 mmHg scores zero; 160.1 mmHg or another value above 160 scores one. This is a score boundary, not a complete hypertension assessment or blood-pressure target, and one reading does not establish a diagnosis.
The original definition is chronic dialysis, kidney transplantation, or serum creatinine at least 200 µmol/L, approximately 2.26 mg/dL. It is a fixed historical criterion; this page does not collect laboratory values and must not silently substitute eGFR, creatinine clearance, or another chronic-kidney-disease definition.
Sources: [1]
The original definition is chronic hepatic disease such as cirrhosis, or biochemical evidence of significant hepatic derangement: bilirubin above twice the upper limit of normal together with AST, ALT, or alkaline phosphatase above three times the upper limit of normal. An isolated laboratory value or symptom should not be reclassified without applying the full definition.
Sources: [1]
The 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 routine INR monitoring to titrate anticoagulation, so this criterion does not measure their adherence or exposure.
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 score groups were small and uneven, with no participants at scores 7–9 and only two at score 6; the static table is context, not a personalized probability lookup. Rates vary by cohort, treatment era, anticoagulant, outcome definition, and follow-up, and later validation and meta-analysis found variable calibration.
Some older publications used 3 or more as a prompt to review bleeding factors, but it is not a universal event probability, dynamic result label, or treatment threshold. Current U.S. and ESC guidance does not allow a bleeding score alone to decide oral-anticoagulation eligibility or withdrawal; bleeding factors should be identified and revisited.
They address different outcomes. HAS-BLED groups historical bleeding-risk factors; classic CHA₂DS₂-VASc groups stroke and systemic-thromboembolism factors in established AF or flutter. Their totals must not be subtracted or balanced into a net score, and this page does not calculate either stroke risk or net clinical benefit.
No. It does not diagnose AF or bleeding, establish an indication or contraindication, choose VKA or DOAC therapy, recommend a dose, plan INR monitoring, or instruct a person to start, stop, withhold, or change treatment. Those decisions require the applicable clinical pathway and complete patient assessment.
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Disclaimer
Educational and informational reference only. Not intended to replace professional medical advice, diagnosis, treatment, or independent verification.