Roger Federer (born 8 August 1981) is a Swiss professional tennis player who is currently ranked world no. 4 by the Association of Tennis Professionals (ATP). He has been ranked inside the top 10 continuously since October 2002 and the top 20 since April 2001. Numerous commentators, pundits, and former and current players of the sport regard Federer as the greatest tennis player of all time.

He holds several mens world records of the Open Era: holding the world no. 1 position for 302 weeks overall, including a 237-consecutive-week stretch at the top from 2004 to 2008; winning 17 Grand Slam singles titles; reaching each Grand Slam Final at least five times (an all-time record); and reaching the Wimbledon final eight times. He is one of seven men, and one of four in the Open Era, to capture the career Grand Slam. Federer also shares the Open Era record for most titles at the Australian Open with Agassi and Novak Djokovic , at Wimbledon with Pete Sampras and at the US Open with Jimmy Connors and Sampras .

Federer has appeared in 24 mens Grand Slam finals, with 10 in a row, both records, and appeared in 18 of 19 finals from the 2005 Wimbledon Championships through to the 2010 Australian Open. He is the only man to reach at least the semifinals of 23 consecutive Grand Slam tournaments, from the 2004 Wimbledon Championships through the 2010 Australian Open. At the 2014 French Open, he reached a record 58th consecutive Grand Slam tournament. Earlier at the 2014 Australian Open, he extended his record to 34th Grand Slam semi-final and reached a record 41st Grand Slam quarter-final (shared with Connors), and at the 2013 French Open reached a record 36th consecutive Grand Slam quarter-final. He has also won the most matches, 267, in mens Grand Slam tournaments and is the only player to record 60+ wins each at all the Grand Slam tournaments.

Federers ATP tournament records include winning six ATP World Tour Finals (an all-time record), playing in the finals at all nine ATP Masters 1000 tournaments (a record shared with Djokovic and Nadal), and having won the most prize money of any player in history, with over $80,000,000. Federer holds the record for most tiebreaks won and best winning percentage in these situations. He also won the Olympic gold medal in doubles with his compatriot Stanislas Wawrinka at the 2008 Summer Olympic Games and the Olympic silver medal in singles at the 2012 Summer Olympic Games. He spent eight years (2003–2010) continuously in the top 2 in the year-end mens rankings and ten (2003–2012) in the top 3. Federer is the first tennis player, male or female, to earn more than 50 million US dollars in prize money.

Federer has won the ATPWorldTour.com Fans Favourite Award a record eleven times straight (2003–2013) and the Stefan Edberg Sportsmanship Award (voted for by the players) a record nine times (2004–2009, 2011–2013), both being awards indicative of respect and popularity. He also won the Arthur Ashe Humanitarian of the Year Award twice in 2006 and 2013. He was named the Laureus World Sportsman of the Year for a record four consecutive years (2005–2008). Federer is at times referred to as the Federer Express, shortened to Fed Express or FedEx, the GOAT, and the Swiss Maestro, or just Maestro.