The 2018 ATP World Tour calendar comprised the Grand Slam tournaments (supervised by the International Tennis Federation (ITF)), the ATP World Tour Masters 1000, the ATP Finals, the ATP World Tour 500 series, the ATP World Tour 250 series and the Davis Cup (organized by the ITF).

Also included in the 2018 calendar are the Hopman Cup and the Next Gen ATP Finals, which do not distribute ranking points.

[1][2] These tables present the number of singles (S), doubles (D), and mixed doubles (X) titles won by each player and each nation during the season, within all the tournament categories of the 2018 ATP World Tour: the Grand Slam tournaments, the ATP Finals, the ATP World Tour Masters 1000, the ATP World Tour 500 series, and the ATP World Tour 250 series.

The players/nations are sorted by: The following players won their first main circuit title in singles, doubles or mixed doubles: The following players defended a main circuit title in singles, doubles, or mixed doubles: The following players achieved a career-high ranking this season in the top 50 (bold indicates players who entered the top 10 for the first time): These are the ATP rankings and yearly ATP Race rankings of the top 20 singles players, doubles players and doubles teams at the current date of the 2018 season.

Note: Both the Wimbledon semifinal between Djokovic and Nadal, and the Australian Open men's singles final were contested in their entirety indoors despite being played at traditional outdoor events Following is a list of notable players (winners of a main tour title, and/or part of the ATP rankings top 100 [singles] or top 100 [doubles] for at least one week) who announced their retirement from professional tennis, became inactive (after not playing for more than 52 weeks), or were permanently banned from playing, during the 2018 season: