Basketball Clock Rules

Depending on the league, basketball rules dictate using both quarters and halves to break up the game. The official time limit varies based on the league, generally increasing in length as the talent increases. While the game clock increases, the shot clock decreases to ensure a fast-paced game. The NBA adopted instant replay to review shots that are taken close to the end of a period. A shot that was taken before the buzzer sounds is counted.

  1. Game Clock

    • Basketball leagues dedicate different amounts of time to a game. Generally, a high school basketball game has eight minutes per quarter, a college game has two 20-minute halves, an NBA game has 12-minute quarters and international basketball has 10-minute quarters. The game clock is stopped when the referee blows the whistle. In some leagues, the clock stops after a basket is made when there is under a certain amount of time left in a quarter or half. When the final buzzer sounds, the team in the lead is declared the winner. If the game is tied, there will be an overtime period, which is usually five minutes.

    Shot Clock

    • The shot clock was first used by the Syracuse Nationals of the NBA in 1954. Its purpose was to quicken the game and create more scoring. The NBA uses a 24-second shot clock. College basketball uses a 35-second shot clock. Some high schools use a shot clock, which is generally 60 seconds. The team in possession of the ball must shoot it before the shot clock expires. If the ball hits the rim, or if there is a change in possession, the shot clock resets. An air ball, or a shot that only hits the backboard will not reset the clock.

    Buzzer Beaters

    • As long as a player takes and makes a shot before the game or shot clock expires, it will be counted. The ball must be out of the player's hand when the clock hits zero, or else it will be considered a shot clock violation, or the period will end and the goal will not count. Once the game clock has expired, no one on the offensive team can tip the ball into the goal, or else the shot will not count.