How WTA Rankings Work
How WTA Ranking Points Work and When They Drop Off
A WTA singles ranking is not an average of every event a player enters. It is the total of her best results from a limited number of tournaments inside a rolling 52-week window, and it changes every week as old results drop out.
The 18 results that count
According to the WTA's official rankings page, a singles ranking is built from a maximum of 18 tournaments; doubles rankings use the best 12 results. The rulebook fixes part of that tally: the four Grand Slams and the biggest WTA 1000 events count for every player who is entered in them, whether she plays well or not. The remaining places are filled by her best results at other WTA 1000, WTA 500, WTA 250, WTA 125 and ITF events.
If a player qualifies for the WTA Finals, that result is added to her total as a bonus tournament on top of the 18. The system is cumulative, so a deep run at one big event can outweigh several early losses elsewhere.
Why points "drop off"
Points stay on a player's record for 52 weeks. When the same tournament comes round again a year later, last year's points disappear from her total, which is what commentators mean by "defending points". A player who won a WTA 500 event last season must do well there again, or earn the same points somewhere else that year, to keep her ranking where it is.
That is why a ranking can fall even during a good week. If a player reaches a quarter-final but made the final at the same event a year ago, her total goes down. Results from the WTA Finals follow their own drop-off date, set in the rulebook around the following year's Finals.
What the ranking decides
The ranking is used for almost everything that happens before a ball is hit. Entry lists for tournaments are filled in ranking order, so the ranking decides who gets directly into a main draw and who has to play qualifying. Seeds are also set by ranking: the WTA uses the singles rankings from the week before the tournament begins. If two players are tied, the higher ranking from the previous week decides, and after that the order is drawn at random.
For exact point values per round, check the current WTA rankings explanation on wtatennis.com, which is the official source and is updated for each season.
Rules, point tables and prize money are set by the tours and the ITF for each season. Check the official source named in the text before relying on a figure.
