Coronary artery calcium (CAC) accumulation, a marker of atherosclerosis burden, differs significantly among patients of different ethnicities. It has been proposed that CAC scores can be used to assess the number of life years lost or gained by an individual with a given amount of coronary artery calcium. Therefore, we sought to develop a method to calculate the coronary age of an individual based on the extent of CAC in this subject compared to that of individuals of the same race, age and sex. We used median CAC scores from previously published data from the Multi-Ethnic Study of Atherosclerosis (MESA) to derive the predicted coronary age of subjects from 4 ethnic groups (White, Black, Hispanic and Chinese) of both sexes. With this method a 50-year-old white man with a CAC score of 40 has a coronary age of a 61-year-old white man; for a black man with a score of 40 the coronary age is 70. This method should allow patients to better understand the prognostic significance of their test results and may ensure a better compliance with preventive regimens.