The HeRS (Hemorrhage Risk Stratification) calculator is an application that aids in determining the probability of hemorrhagic transformation of acute ischemic stroke in patients with an indication for anticoagulation. It is a prospectively validated score.

The HeRS score is a prospectively validated equation based on continuous variables of age, renal function, and stroke size. The equation is complex and cannot be performed easily or quickly with paper or with an ordinary calculator. Determining the probability of hemorrhagic transformation of acute ischemic stroke is clinically useful as risk of hemorrhage often needs to be weighed against risk of recurrent stroke in deciding on whether or not to anticoagulate in the acute clinical setting. The HeRS score provides one of these valuable pieces of data- the likelihood of hemorrhagic transformation. Using the mobile application, the HeRS score can be accurately and easily determined rapidly.