A photo finish occurs in a sporting race when multiple competitors cross the finishing line at nearly the same time. As the naked eye may not be able to determine which of the competitors crossed the line first, a photo or video taken at the finish line may be used for a more accurate check. Photo finishes make it less likely that officials will declare a race a dead heat.

A dead heat is a rare situation in various racing sports in which the performances of competitors are judged to be so close that no difference between them can be resolved. The result is declared a tie and the competitors are awarded a joint ranking. Dead heats can occur in both head-to-head races and competitions where competitors race sequentially and are ranked by finishing time.