Aspirin bleeding-risk calculator

A New Zealand tool to help clinicians show patients estimates of the benefits and harms to them of taking aspirin to reduce the risk of cardiovascular events.

Aspirin bleeding-risk calculator

This is a New Zealand-based online tool to help estimate a patient’s 5-year risk of a cardiovascular disease (CVD) event and the risk of a major bleed for primary prevention patients with and without aspirin.

You can find the aspirin bleeding risk calculator here

This tool helps clinicians show patients estimates of the benefits and harms for them of taking aspirin. The tool informs and helps them decide on taking aspirin, as it is a decision only they can make.

It takes into account whether they are on medications and/or have any other health conditions that can influence bleeding and CVD events. It is based on a New Zealand cohort of 245,028 patients. The data may not be relevant to patients in countries outside New Zealand.

Limitations of the calculator

The calculator is NOT suitable for the following patients 
  • aged less than 30 years
  • aged 75 years or more
  • with established CVD
  • with heart failure
  • with atrial fibrillation
  • with familial hypercholesterolaemia
  • with chronic kidney disease (eGFR <30)
  • with diabetes with overt nephropathy OR diabetes with other renal disease (eGFR <45)
  • with an intracerebral bleed
  • who are currently receiving aspirin, other antiplatelet medication, or anticoagulant medication


  1. Personalized prediction of cardiovascular benefits and bleeding harms from aspirin for primary prevention: a benefit–harm analysis. Ann Intern Med (2019).
Credits: Health Navigator Editorial Team.