The 100 metres at the World Championships in Athletics has been contested by both men and women since the inaugural edition in 1983. It is the second most prestigious 100 m title after the 100 metres at the Olympics. The competition format typically has two or three qualifying rounds leading to a final between eight athletes. Since 2011 a preliminary round has been held, where athletes who have not achieved the qualifying standard time compete to enter the first round proper.
The championship records for the event are 9.58 seconds for men, set by Usain Bolt in 2009, and 10.70 seconds for women, set by Marion Jones in 1999. The men's world record has been broken or equalled at the competition three times: by Carl Lewis in 1987 and 1991, and by Usain Bolt in 2009.Ben Johnson beat Lewis in the 1987 final, but his win and record were subsequently rescinded after his admission to long-term steroid use. Lewis's mark, which equalled the standing record at the time, was never officially ratified by the IAAF as a world record. The women's world record has not yet been beaten at the championships.
The United States is the most successful nation in the discipline, having won fifteen gold medals. Jamaica are a clear second with six gold medals. East Germany, with two, is the only other nation to have won multiple titles.