The Boston Celtics and Miami Heat tipoff Game 2 of the 2022 Eastern Conference Finals.
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How Long is a Basketball Game & How Shot Clocks Revolutionized The Sport

Basketball is one of the most popular sports in the world. It's played in pretty much every country you can think of. The National Basketball Association, which is a member of USA Basketball and recognized by FIBA (International Basketball Federation) as the national governing body for basketball in the United States, consists of teams each worth billions of dollars. The NBA Finals alone draws tens of millions of viewers every year.

Many fans watch basketball because it's basically nonstop action. But before LeBron James was gliding coast-to-coast for a dunk or before Michael Jordan was hitting clutch jump shots or even before Steph Curry was swishing three-pointers from the half-court line, basketball was boring and in decline in the 1950s.

The implementation of the shot clock essentially saved the game and put fans in the seats when it was introduced. Prior to it, NBA teams could hold the ball for as long as they'd like once they had a lead. The result? Final scores like 19-18 when the Fort Wayne Pistons defeated the Minneapolis Lakers in 1950. Dean Smith made a living implementing a "four corners" stall offense in college that was unstoppable because there was no shot clock.

The game of basketball and its rules — for which there are plenty — have been revised throughout the years to put the best possible product on the court possible.

That being said, one pressing question many new fans ask is: How long is a basketball game? That answer varies because different rules exist for the many levels of basketball that include professional basketball, Olympic basketball, college basketball, high school and youth basketball.

How Long Is an NBA Basketball Game?

Jimmy Butler drives the lane against the Boston Celtics.

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NBA games are divided into four quarters, each of which last 12 minutes long. That means there are 48 total minutes of play in a single game. There's a 15-minute halftime break to allow players to rest in between the second and third quarter. If the game is tied at the end of regulation, there's a 5-minute overtime period.

The average length of a basketball game in the NBA lasts anywhere from 2-3 hours after factoring in team timeouts, clock stoppages for substitutions, replay reviews, shooting fouls, TV timeouts for commercial breaks, halftime breaks, breathers and other stoppages. Most game lengths are about two and a half hours.

How Long Is a College Basketball Game?

Kansas guard Ochai Agbaji drives against North Carolina.

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College basketball games are slightly different. NCAA basketball games for men consist of two 20-minute halves, adding up to 40 total minutes of game time. Each overtime period is five minutes long. NCAA women's college games are played in four 10-minute quarters just like WNBA games are. The amount of time it takes to complete a game is about two hours.

Most high school basketball games in the United States are played in 8-minute quarters, but that varies from state to state.

How The Shot Clock Changed Basketball

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Back in 1954, the Syracuse Nationals owner Danny Biasone and general manager Leo Farris began implementing a 24-second shot clock during scrimmages. The result was a faster, higher-scoring game that the NBA officially adopted for the 1954-55 season.

The shot clock completely revolutionized the professional basketball game. Points soared, as did attendance. Some said it saved basketball, others said it rescued it. Either way, everyone was in favor of it.

The NBA currently uses a 24-second shot clock. This means teams must shoot the ball before that time expires, or else they lose possession of the ball. The shot clock resets to 14 seconds in the NBA after an offensive rebound on a missed shot or free throw that hit the rim.

The National Collegiate Athletic Association (NCAA) currently uses a 30-second shot clock for both men and women's basketball matches. The league introduced a 45-second shot clock in 1985 and reduced it to 35 second in 1993 before landing on a 30-second shot clock in 2015.

How Many Timeouts Are In a Basketball Game?

Wes Unseld JR. instructs his team in the middle of a game against the Dallas Mavericks.

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The game clock stops a whole lot in the NBA, which is why the league has tried to speed up games by limiting the number of timeouts teams can call. As of the 2017-18 season, NBA teams are allowed seven timeouts per game. Each team is also only afforded two timeouts in the final three minutes, a change of pace from when it could call three timeouts in the final two minutes.

Each timeout in these professional games last 75 seconds. The NBA used to allow 100-second timeouts and "20-second" timeouts that were actually more like 60 seconds.

The NCAA permits three 30-second timeouts per game, two of which can roll over into the second half. In addition, teams get one 60-second timeout that can be called at any time of the game. High school games follow a similar model to college rules.

The Longest Game In NBA History

There's a reason the NBA has stricter time constraints now. Look no further than a game played on January 6, 1951, for just why that is.

The Rochester Royals and Indianapolis Olympians squared off in a (not so epic) game that wound up lasting a total time of 78 minutes and six overtimes, good for the longest NBA basketball game in history. The bout, which took place at Edgerton Park Arena in Rochester, New York, was ultimately won by the Olympians.

What's horrendous is that just 18 points were scored in the timeframe of the entire six overtimes. Neither team scored in the second and fourth overtimes. Why? Because the team who started with the ball tended to wait for the clock to run out before throwing up the final shot.

From the Rochester Democrat: "[For] more than 26 of the 30 overtime minutes, the ball stayed neatly tucked away under an arm of a Royal or Olympian player. One or another player just stood there with the score tied, waiting out the clock for a last-second 'nothing-to-lose' shot...Customers who complained were burned up at the unchallenged freeze. For the Olympians, it sure wasn't good basketball, but it paid off."

Booooooring. That's a far cry from the time Tracy McGrady scored 13 points in 33 seconds, a feat that actually happened in a professional basketball league and is still remarkable.

The Longest Game in NCAA History

As for college basketball, the longest game in NCAA men's basketball history was a similar 75-minute, seven-overtime game between Bradley and Cincinnati in 1981. That came before a shot clock was implemented as well.

The sport of basketball has come a long way since the pre-shot clock days. I'm not sure we'll ever see another six- or seven-overtime game, and that's probably for the best. We arguably have the best collection of basketball players ever and regular-season games are starting to become as exciting as the playoffs. Not to mention, the average points per game per team is the highest its been since the 1980s, so sit back and enjoy the fireworks.

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