Editing Shot clock (section)

==Operation==
The shot clock begins counting down when a team establishes possession, and stops any time the game clock stops (e.g., [[time-out (sport)|timeouts]], violations, fouls). The offensive team must attempt to score a field goal before the shot clock expires; otherwise, the team has committed a '''shot clock violation''' (also known as a '''24-second violation''' in leagues with a 24-second shot clock) that results in a [[Turnover (basketball)|turnover]] to their opponents. An important distinction is that there is no violation if the ball is in flight to the basket when the shot clock expires, as long as the ball leaves the player's hand before the shot clock expires and the ball proceeds to go into the basket or touch the basket rim.

The shot clock resets to its full length at the start of each period and whenever possession changes to the opposite team such as after a basket is scored, the defense [[steal (basketball)|steals]] the ball or recovers a [[rebound (basketball)|rebound]], or the offense commits a [[foul (basketball)|foul]] or [[violation (basketball)|violation]]. The full length varies by country, level of play, and league; see the table [[#Shot clock length in basketball|below]]. The shot clock does not reset if a defender makes short contact with the ball (e.g., an attempted steal or a tipped pass) but the offense retains possession, or if a shot attempt misses the rim entirely and [[Air ball|airball]]s. The shot clock also resets when the offense retains possession after a missed field goal or free throw, or on certain fouls or violations that give the offense an inbounds pass in their frontcourt. 

If the offensive team is fouled and the penalty does not include free throws but just an in-bounds pass, the shot clock is reset. There are several cases where the offense is not given a full 24 seconds. The shot clock is instead set to 14 following an offensive rebound.<ref name=NBA7>{{Cite web
|url=http://official.nba.com/rule-no-7-24-second-clock/
|title=RULE NO. 7: Shot Clock
|date=15 October 2018
|publisher=NBA
}}</ref>{{rp|7-IV-d}} FIBA adopted this in 2014 and the NBA adopted in 2018.<ref>[http://www.fiba.basketball/news/nba-implements-fibas-14-second-shot-clock-rule NBA implements FIBA's 14-second shot clock rule], FIBA.basketball</ref> The WNBA also observes this rule. In several other cases where the offense inbounds the ball in its frontcourt (such as a foul by the defense not resulting in free throws), the offense is guaranteed 14 seconds.<ref name=NBA7 />{{rp|7-IV-e}} The shot clock is increased to 14 if it showed a shorter time.

On a held ball (whether decided by a [[jump ball]] or a [[possession arrow]]), the state of the shot clock depends on which team gets possession of the ball.
*If the defensive team acquires possession, the shot clock is reset, as it is on any other change of possession.
*If the offense retains possession, the shot clock is not reset, because there was no change of possession. However, in Euroleague, the NBA, and WNBA, the shot clock is topped up to 14 seconds, as described above for a frontcourt inbounds pass.

Near the end of each period, if the shot clock would ordinarily display more time than there is remaining in the period, the shot clock is switched off. During this time, a team cannot commit a shot clock violation.

The shot clock apparatus itself is considered out of bounds and not part of the [[Backboard (basketball)|backboard]].  The shot clock operator sits at the scorer's table. This is usually a different person from the scoreboard operator, as the task requires concentration during and after the shot attempt. In the [[2016-17 NBA season]], a new 'official timekeeper' deal for the NBA with Swiss watch manufacturer [[Tissot]] introduced technology to unify the keeping of the shot clock and the game clock.<ref>{{cite web|title=NBA, watchmaker Tissot announce multiyear partnership|date=5 October 2015 |url=https://www.espn.com/nba/story/_/id/13813208/nba-watchmaker-tissot-announce-multi-year-partnership|publisher=ESPN|access-date=February 23, 2016}}</ref> Tissot also became official timekeeper for the WNBA in the 2017 season.

===Collegiate rules===
American collegiate basketball uses a 30-second shot clock, while Canadian university basketball uses a 24-second clock.

In men's collegiate basketball, there was initial resistance to the implementation of a shot clock for men's [[National Collegiate Athletic Association|NCAA]] basketball, due to fears that smaller colleges would be unable to compete with powerhouses in a running game. However, after extreme results like an 11–6 [[Tennessee Volunteers basketball|Tennessee]] win over [[Temple Owls men's basketball|Temple]] in 1973, support for a men's shot clock began to build.<ref name="tntempleshotclock">{{cite web|url=http://www.govolsxtra.com/news/2007/nov/07/night-crawler-temple-set-stage-for-time-clock-in/|title=Temple set stage for shot clock|last=Strange|first=Mike|date=2007-11-07|publisher=[[E. W. Scripps Company|Scripps Interactive Newspaper Group]]|archive-url=https://web.archive.org/web/20071109195519/http://www.govolsxtra.com/news/2007/nov/07/night-crawler-temple-set-stage-for-time-clock-in/|archive-date=November 9, 2007|access-date=January 13, 2012|work=The Knoxville News-Sentinel}}</ref> The NCAA introduced a 45-second shot clock for the [[1985-86 NCAA Division I men's basketball season|1985-86]] season;<ref name=adpsclk>{{cite news|url=https://news.google.com/newspapers?id=vVhWAAAAIBAJ&sjid=Ee8DAAAAIBAJ&pg=6871%2C1087852 |work=Spokesman-Review |location=(Spokane, Washington) |agency=Associated Press |last=Crowley |first=Anne S. |title=NCAA adopts shot clock for next year |date=April 3, 1985 |page=C3}}</ref> several conferences had experimented with it for the two seasons prior.<ref name=scpohld>{{cite news|url=https://news.google.com/newspapers?id=7ldWAAAAIBAJ&sjid=7-4DAAAAIBAJ&pg=6603%2C3379474 |work=Spokesman-Review |location=(Spokane, Washington) |agency=Associated Press |last=Cour |first=Jim |title=Shot clock put on hold by colleges |date=April 5, 1984 |page=25 }}</ref> It was reduced {{nowrap|to 35 seconds}} in the [[1993–94 NCAA Division I men's basketball season|1993–94]] season,<ref>[http://web1.ncaa.org/web_files/stats/m_basketball_RB/2008/2008RB.pdf Official 2008 NCAA Men's Basketball Records Book], p. 278</ref> and {{nowrap|30 seconds}} in the [[2015–16 NCAA Division I men's basketball season|2015–16]] season.<ref>{{cite news|url=https://www.espn.com/mens-college-basketball/story/_/id/13037928/ncaa-announces-rule-changes-2015-16-including-30-second-shot-clock-fewer-outs |title=Shorter shot clock, fewer timeouts among changes coming in 2015-16 |work=ESPN.com |date=June 8, 2015 |access-date=June 9, 2015}}</ref> The [[National Association of Intercollegiate Athletics|NAIA]] also reduced the shot clock to 30 seconds starting in 2015–16.<ref>{{cite news|url=http://newsok.com/article/feed/850159|title=Rule changes for NAIA, too|work=The Salina Journal|agency=Associated Press|date=June 10, 2015|via=News OK}}</ref>

Women's collegiate basketball (at the time sanctioned by the [[Commission on Intercollegiate Athletics for Women]]) used a 30-second shot clock on an experimental basis in the 1969–70 season, officially adopting it for the 1970–71 season.<ref>[http://web1.ncaa.org/web_files/stats/w_basketball_RB/2008/2008RB.pdf Official 2008 NCAA Women's Basketball Records Book], p. 245</ref>

The NCAA specifies 20 seconds rather than 30 after stoppages where the ball is already in the frontcourt. In 2019, it added offensive rebounds to this list.<ref>{{cite web|url=https://www.ncaa.com/news/basketball-men/article/2019-11-05/mens-college-basketball-rule-changes-know-about-season|title=The men's college basketball rule changes to know about this season|first=Andy|last=Katz|publisher=NCAA|date=November 5, 2019}}</ref>

===US high schools rules===
The [[National Federation of State High School Associations]] (NFHS), which sets rules for high school basketball in the U.S., does not mandate the use of a shot clock, instead leaving the choice to use a clock and its duration up to each individual state association. In concert with this, the "stall ball" strategy can be used in a state or league, but depending on the organization, itself comes with restrictions on its use by the game officials, with overuse of it often being whistled as a foul or an unsportsmanlike act. Others may allow stalling completely, at the risk of fan disinterest.

As the cost of a shot clock system can be cost-prohibitive, its use in high schools has been debated on that consideration and not the flow of the game. While previous proposals for a national shot clock had been denied by the NFHS as recently as 2011,<ref name=usat>{{cite news |url= https://www.usatoday.com/sports/preps/basketball/2011-05-15-high-school-shot-clock_N.htm |title=Focus on high school shot clock heats up as states make move – USATODAY.com |first= Jim |last=Halley |work=[[USA Today]] |date=May 5, 2011|issn=0734-7456 |access-date=December 31, 2011}}</ref> in the spring of 2021 the NFHS agreed to allow its member associations the option of a shot clock, with a mandatory 35-second duration, starting in 2022–23.<ref>{{cite press release|url=https://www.nfhs.org/articles/shot-clock-allowed-by-state-adoption-for-high-school-basketball-in-2022-23/ |title=Shot Clock Allowed By State Adoption for High School Basketball in 2022-23 |publisher= National Federation of State High School Associations |date=May 13, 2021 |access-date=August 12, 2021}}</ref>

As of August 2021, 11 states either require a shot clock in high school competition or will begin using one starting in 2022–23: California, Georgia, Iowa, Maryland, Massachusetts, Nebraska (Class A only, expanded to Class B in 2023-24 and to all classes in 2024-25), New York, North Dakota, Rhode Island, South Dakota, and Washington.<ref name=usat/><ref>{{cite web|url=https://www.press-citizen.com/story/sports/high-school/2021/08/10/shot-clock-iowa-high-school-basketball-ihsaa-ighsau-statement-2022-23/5550888001|title=IHSAA, IGHSAU release joint statement on shot clock coming to Iowa high school basketball|last=Southard|first=Dargan|work=[[Iowa City Press-Citizen]]|date=August 10, 2021|accessdate=2021-08-12}}</ref> Before 2022–23, the District of Columbia used a 30-second shot clock for public school [[District of Columbia Interscholastic Athletic Association|(DCIAA)]] competition, charter school competition (as of 2018–19), and for the [[District of Columbia State Athletic Association|DCSAA]] State Tournament, where public, private, and charter schools compete for the championship of the District of Columbia.

===Shot clock length===
====Shot clock length in basketball====
{| class="wikitable"
|-
!Organization
!Duration
|-
|[[National Basketball Association|NBA]] 
|rowspan=4|24 seconds
|-
|[[Women's National Basketball Association|WNBA]]
|-
|[[Women's Basketball Development Association|WBDA]]
|-
| [[U Sports]] (Canadian universities)
|-bgcolor="#f0f0f0"
| [[National Collegiate Athletic Association|NCAA]], [[National Association of Intercollegiate Athletics|NAIA]], [[United States Collegiate Athletic Association|USCAA]], etc.
| 30 seconds
|-
| United States high school basketball
| 35 seconds (some states only)
|-bgcolor="#f0f0f0"
| [[FIBA]]
| 24 seconds<br>12 seconds ([[3x3 (basketball)|3x3 half-court]])<ref>{{cite web|url=https://archive.fiba.com/downloads/v3_abouFiba/3x3/3x3RulesOfTheGame.pdf |archive-url=https://web.archive.org/web/20240812123641/https://archive.fiba.com/downloads/v3_abouFiba/3x3/3x3RulesOfTheGame.pdf |url-status=dead |archive-date=August 12, 2024 |title=Article 8 Stalling |work=3x3 Rules of the Game |publisher=[[FIBA]] |page=2 |date=January 13, 2012 |access-date=April 11, 2013}}</ref>
|}

====Shot clock length in other sports====
{| class="wikitable"
!Sport
!Organization
!Duration
|-
|rowspan=5|[[Lacrosse]]
|[[Major League Lacrosse|MLL]] ([[MLL–PLL merger|defunct]])
|60 seconds
|-
|[[Premier Lacrosse League|PLL]]
|52 seconds
|-
|[[National Lacrosse League|NLL]]
|30 seconds
|-
|[[NCAA]] Men's
|80 seconds<ref name="NCAA lax shot clock">{{cite news|last=Lee|first=Edward|title=Time is now: NCAA approves 80-second shot clock for men's lacrosse|url=https://www.baltimoresun.com/sports/lacrosse-blog/bs-sp-mens-lacrosse-to-get-80-second-shot-clock-for-2019-story.html|newspaper=[[The Baltimore Sun]]|date=September 12, 2018|access-date=February 13, 2019|archive-date=February 14, 2019|archive-url=https://web.archive.org/web/20190214061536/https://www.baltimoresun.com/sports/lacrosse-blog/bs-sp-mens-lacrosse-to-get-80-second-shot-clock-for-2019-story.html|url-status=dead}}</ref>
|-
|[[NCAA]] Women's
|90 seconds<ref name="NCAA lax shot clock" />
|-
|[[Australian rules football]]
|[[Australian Football League|AFL]]
|30 seconds<ref>{{Cite web |title=AFL to crack down on deliberate time wasters |url=https://www.afl.com.au/news/139466/afl-to-crack-down-on-deliberate-time-wasters |access-date=2022-08-13 |website=afl.com.au |date=6 July 2018 |language=en}}</ref>
|-bgcolor="#f0f0f0"
|[[Ringette]]
|[[International Ringette Federation]] (IRF)
|30 seconds
|-
|[[Water polo]]
|[[International Swimming Federation|FINA]]
|30 seconds
|-bgcolor="#f0f0f0"
|[[Canoe polo]]
|[[International Canoe Federation|ICF]]
|60 seconds
|-
|[[Ten-pin bowling]]
|[[Professional Bowlers Association|PBA]]
|25 seconds (only used on TV)
|-bgcolor="#f0f0f0"
|[[Korfball]]
|[[International Korfball Federation|IKF]]
|25 seconds
|-
|[[Tennis]]
|[[International Tennis Federation|ITF]]
|25 seconds
|-
|[[Snooker]]
|[[Snooker Shoot Out]]
|15 seconds (first five minutes)<br>10 seconds (last five minutes)
|-bgcolor="#f0f0f0"
|[[Carom billiards]]<br>([[three-cushion billiards]])
|
*[[UMB World Three-cushion Championship|World Championship]]
*[[CEB European Three-cushion Championship|European Championship]]
*[[Three-Cushion World Cup|World Cup]]
|40 seconds<ref>{{cite web |url=http://files.umb-carom.org/Public/Rules/RULES_3Cushion_INDIVIDUALS.pdf |title=Official Tournament Rules |page=4 |work=[[Union Mondiale de Billard]] (UMB) |access-date=April 30, 2017}}</ref><br>(3 time-outs (40 sec.) possible)
|-
|[[Poker]]
|[[World Poker Tour]]
|30 seconds<br>99 seconds (optional)<ref>{{Cite web|title = Gamingsupport.com: Poker Shot Clock |url = https://gamingsupport.com/collections/live-table-game-accessories/products/poker-shot-clock|website = www.gamingsupport.com|access-date = January 30, 2020}}</ref>
|-
|}

===Related concepts===
A related rule to speed up play is that the offensive team has a limited time to advance the ball across the half-court line (the "[[Time line (basketball)|time line]]").