The International Eight Metre class are class of racing yachts. Eight Metre boats are a construction class, meaning that the boats are not identical but are all designed to meet specific measurement formula, in this case International rule. Before WW II, Eights were the most prestigious international yacht racing class and they are still raced around the world. "Eight metre" in class name does not, somewhat confusingly, refer to length of the boat, but product of the formula. 8mR boats are on average some 15 metres long. Between 1907 and 2008 approximately 500 8mR boats were built, 177 of them have survived until today.

The International rule, also known as the Metre rule, was created for the measuring and rating of yachts to allow different designs of yacht to race together under a handicap system. Prior to the ratification of the International rule in 1907, countries raced yachts under their own national rules and international competition was always subject to various forms of subjective handicapping.