BRIS uses an objective, computer-precise method to make a final time projection rating. This rating then allows a handicapper to compare the relative speed of different horses in different races and at different tracks. These ratings are calculated using proprietary techniques and algorithms that have been tested and proven over hundreds of thousands of races. Because the ratings are "fully adjusted" (reflecting both daily and track-to-track variants), they are comparable across all North American racetracks. For males 3 years old and older, a typical speed rating in a grade I race is 106, for an open $10,000 claiming race winner it’s 88, and for a $10,000 maiden claiming winner it’s 75.

This rating measures a horse's actual performance in a race--the higher the number, the better the performance. Class ratings are calculated daily by Bloodstock Research Information Services (BRIS) for every horses that starts in a North American race. The rating provides a convenient means for comparing the relative merits of each horse's recent races to that of it's competitors. The male winners of a grade I race typically will have a rating in the 123-127 range, an open claiming race for older males will see ratings in the 114-115 range, and a maiden claiming race for older males may be in the 108-109 range.