2023 World Aquatics Championships

The 2023 World Aquatics Championships, the 20th edition of the World Aquatics Championships, were held in Fukuoka, Japan, from 14 to 30 July 2023. Originally scheduled to be held in 2021 as the 19th championships, the championships were postponed until May 2022 in response to the rescheduling of the 2020 Summer Olympics in Tokyo to 2021 due to the COVID-19 pandemic. The event was pushed back a second time to 2023 due to ongoing travel restrictions and safety measures in place in Japan. In its place, Budapest hosted the 19th Championships from 18 June to 3 July 2022, while the originally scheduled 2023 championships in Doha, Qatar, were moved to 2024.

It was the second time Fukuoka hosted the event having previously held the 9th World Aquatics Championships in 2001, with South Africa's Roland Schoeman (swimming) and Brazil-Spain's Felipe Perrone (water polo) the only two athletes to compete in both the 2001 and 2023 championships.

The championships included 2,392 athletes competing from 192 member federations. While originally listed as 195 nations competing, due to the status of their member federation with World Aquatics, athletes from both the Philippines and Kenya were required to compete under the banner 'Suspended Member Federation', while two athletes of Syria competed under the banner 'World Aquatics Refugee Team'. World Aquatics ban on athletes from Russia and Belarus remained in effect for these championships.

These championships were the first edition of the championships to be held under the new World Aquatics branding following the renaming of FINA (French: Fédération Internationale de Natation) in December 2022.

The competition was originally to be held in Budapest, Hungary, in the summer of 2021. This was announced on 19 July 2013, at the biennial General Congress of World Aquatics (then FINA) in Barcelona, the host-city of the 2013 World Aquatics Championships.

However, in March 2015, it was announced that Budapest would instead host the 2017 Championships, after Guadalajara, Mexico, pulled out from the organization of the championships for financial reasons. A new bidding procedure was opened for both the 2021 and 2023 events.

On 9 June 2015, World Aquatics (then FINA) reported it had received expressions of interest for the 2021 and 2023 FINA World Championships from Argentina, Australia (Melbourne or Sydney), China (Wuhan or Nanjing), Germany (two potential cities), Japan, Turkey and Qatar. On 30 June 2015, an information meeting was organised for the nations and cities which had shown interest in bidding. This meeting was attended by representatives of cities from six countries: Abu Dhabi (United Arab Emirates), Buenos Aires (Argentina), Istanbul (Turkey), Nanjing (China), Fukuoka (Japan), Doha (Qatar). Bidding cities were then asked to present FINA with an executed Host City Agreement by October 26, 2015, and to make a formal presentation to the FINA Bureau on November 8, 2015. Australia and Germany were the first two countries to quit the bidding race and were followed by Argentina. Two others, Turkey and United Arab Emirates, had also shown interest, but withdrew before the presentation stage. With all other interested cities formerly withdrawing, on October 2, 2015, FINA executive director Cornel Marculescu confirmed there were three final bidders: Nanjing (China), Fukuoka (Japan), and Doha (Qatar).

On 31 January 2016, each of the bids were presented in a formal presentation at the FINA Bureau meeting in Budapest. After a vote, FINA announced Fukuoka as 2021 hosts and Doha as 2023 hosts.