List of WTA number 1 ranked singles players

The list of WTA number 1 ranked players shows the professional women's tennis players who have been or currently are ranked world No. 1 by the Women's Tennis Association, along with the dates of first reaching and losing that spot. Since the WTA began producing computerized rankings on November 3, 1975, 25 women have reached the highest singles ranking and 36 women the highest doubles ranking. The WTA Rankings are a merit-based method for determining the rankings in women's tennis and the WTA releases ranking points weekly based on how players fared during the previous 52 weeks.

The rankings are sourced by the WTA Media Guide and the WTA website (which usually revises its rankings every Sunday night or Monday morning, except when tournament finals are postponed).

On 11 September 2017, Garbiñe Muguruza and Rafael Nadal made Spain the first country since the United States 14 years ago to simultaneously top both the ATP and the WTA rankings, with Muguruza making her debut in the No. 1 spot. The most recent previous such pair were Serena Williams and Andre Agassi, 28 April to 11 May, 2003.

as of March 12, 2018^[update]
The source for this through the week of January 2, 2012, is the 2012 WTA Tour Official Guide, page 177.

as of March 12, 2018^[update] - current No. 1 player in bold
* Note that Monica Seles is included twice due to change of citizenship.

The source for this through to 2012 is the 2012 WTA Tour Official Guide, page 178.

The source for the following table through the week of January 6, 2012, is the 2012 WTA Tour Official Guide, page 172.

as of March 12, 2018^[update]

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