Novak Djokovic, the current men's singles world No. 1, and the record holder of most weeks spent at the top of the rankings.
The ATP Rankings are the Association of Tennis Professionals' (ATP) merit-based method for determining the rankings in men's tennis. The top-ranked player is the player who, over the previous 52 weeks, has garnered the most ranking points on the ATP Tour. Points are awarded based on how far a player advances in tournaments and the category of those tournaments. The ATP has used a computerized system for determining the rankings since August 23, 1973. Starting in 1979, an updated rankings list is released at the beginning of each week. Since 1973, 26 men have been ranked No. 1 by the ATP, of which 17 have been year-end No. 1. The current world number one is Novak Djokovic from Serbia.
Since the introduction of the rankings, the method used to calculate a player's ranking points has changed several times. As of 2019, the rankings are calculated by totaling the points a player wins in his best eighteen tournaments, subject to certain restrictions. For top players the counting tournaments are the four Grand Slam tournaments, the eight mandatory ATP Masters tournaments, the player's best four eligible ATP Tour 500 tournaments (the non-mandatory ATP Masters 1000 event in Monte Carlo may be substituted for one of these), and his best two results from ATP Tour 250 tournaments. Lower-ranked players who are not eligible for some or all of the top tournaments may include additional ATP 500 and ATP 250 events, and also ATP Challenger Tour, and ITF Men's Circuit tournaments. Players who qualify for the year-end ATP Finals also include any points gained from the tournament in his total, increasing the number of tournaments counted to 19.
Novak Djokovic has spent the most weeks as world No. 1, a total of 319 weeks. Roger Federer has the record of 237 consecutive weeks at No. 1. Novak Djokovic and Pete Sampras hold the record for the most year-end No. 1 rankings, both men achieving the feat six times. Sampras' record was achieved in consecutive years. Patrick Rafter spent the least time at No. 1 (one week).
Novak Djokovic has the record of most ATP rankings points (16,950). Federer in 2004/2006, Nadal in 2010 and Djokovic in 2015 clinched Year-end No. 1 the earliest in the season (September).
Lleyton Hewitt is both the youngest world No. 1 (20 years, 8 months) and youngest year-end No. 1, while Federer is the oldest No. 1 (36 years, 10 months). Djokovic is the oldest year-end No. 1 (33 years, 7 months).
Federer is the player with the longest time span between first and most recent dates at world No. 1 in the history of the ATP. He most recently held the top ranking the week of June 18, 2018, more than fourteen years after first becoming No. 1 on February 2, 2004.
Rafael Nadal has the longest timespan, 11 years, between his first and last year-end No. 1 titles, 2008 and 2019. He is also the only player to be world No. 1 in three decades.
Two players, Ivan Lendl and Marcelo Ríos, have reached No. 1 without previously having won a Grand Slam tournament. Lendl reached No. 1 on February 21, 1983, but did not win his first Grand Slam title until the 1984 French Open. Ríos reached No. 1 on March 30, 1998, but retired without ever having won a Grand Slam singles title, making him the only No. 1 player with that distinction.
Since 1973 when the ATP rankings started, there have been twelve years in which one player held the top spot for the entire year: Jimmy Connors in 1975, 1976, and 1978; Lendl in 1986 and 1987; Pete Sampras in 1994 and 1997; Hewitt in 2002; Federer in 2005, 2006, and 2007; and Djokovic in 2015. In contrast to this, 1999 saw five players hold the No. 1 ranking (the most in any single year): Sampras, Carlos Moyá, Yevgeny Kafelnikov, Andre Agassi, and Rafter.
John McEnroe held the No. 1 ranking on a record 14 occasions, and Sampras is the only other player to have held it on 10 or more occasions with 11 stints.
The statistics are updated only when the ATP website revises its rankings (usually on Monday mornings except when tournament finals are postponed). Weeks' stats will be automatically updated every Monday (UTC).
Roger Federer spent a record 237 consecutive weeks at world No. 1. in the 2000s.
The ATP Tour was suspended from March 16 to August 21, 2020. The ATP Rankings were frozen from March 23 to August 23, 2020; thus that period was not counted towards the total. In that period (22 weeks), the world number one was Novak Djokovic.
John McEnroe finished as the year-end No. 1 for four consecutive years in the 1980s.
Lleyton Hewitt was the youngest male player to hold the world No. 1 ranking, at age 20 in November 2001.
The ATP year-end No. 1 (ATP Player of the Year), in recent decades, has been determined as the player who ends the year as world No. 1 in the ATP Rankings. Prior to the early 1990s this was not always the case, in some instances the "ATP Player of the Year" and the Year-end No. 1 in the rankings were different players. Novak Djokovic and Pete Sampras hold the ATP record of six year-end No. 1 rankings. Six players have stayed at ATP No. 1 in the rankings every week of a calendar year. Roger Federer is the only player to have been ranked No. 1 every week for three consecutive calendar years. Four players (Ivan Lendl, Roger Federer, Novak Djokovic, Rafael Nadal) have achieved year-end No. 1 rankings in non-consecutive years.
^ abcdefghi"Hewitt jubilant as world's No. 1". The Age. November 15, 2002. Retrieved September 6, 2012. Only five other players – Stefan Edberg (1990–91), Ivan Lendl (1985–87), John McEnroe (1981–84), Bjorn Borg (1979–80) and Jimmy Connors (1974–78) – have achieved the mighty feat.
^ abcFord, Bonnie D. (April 9, 2010). "Tennis still imbued in Lendl's blood". ESPN. ESPN Internet Ventures. Retrieved September 6, 2012. In 1988, [Wilander] won a five-set endurance contest, breaking a six-match losing streak to Lendl. The win interrupted Lendl's three-year reign as world No. 1...
^Wilansky, Matt (August 31, 2006). "Inside the numbers". ESPN. ESPN Internet Ventures. Retrieved September 5, 2012. [I]n 1999 he won the French Open title, the only Major that had eluded him. He finished the year ranked No. 1 in the world for the first and only time in his career.