Roger Federer (born 8 August 1981) is a Swiss professional tennis player who is currently ranked world No. 2 in men's singles tennis by the Association of Tennis Professionals (ATP). Federer has won 20 Grand Slam singles titles and has held the world No. 1 spot in the ATP rankings for 302 weeks, including 237 consecutive weeks. After turning professional in 1998, he was continuously ranked in the top ten from October 2002 to November 2016. He re-entered the top ten following his victory at the 2017 Australian Open.