Play clock - wikipedia Play clock This article may require cleanup to meet Wikipedia 's quality standards. The specific problem is : No organization Please help improve this article if you can. ( July 2016 ) A play clock, also called a delay - of - game timer, is a countdown clock intended to speed up the pace of the game, and hopefully the scoring, in American football and Canadian football. The offensive team must put the ball in play by either snapping the ball during a scrimmage down or kicking the ball during a free kick down before the time expires, or else they will be assessed a 5 - yard delay of game ( American football ) or time count ( Canadian football ; that code 's `` delay of game '' is a different infraction ) penalty. If a visible clock is not available or not functioning, game officials on the field will use a stopwatch or other similar device to enforce the rule. In all levels of Canadian football, the offensive team must run a play within 20 seconds of the referee whistling the play in ; in amateur American football, teams have 25 seconds from the time the ball is declared ready for play. In the NFL, teams have 40 seconds timed from the end of the previous down. Before 2008, in college football, the play clock was 25 seconds after the ball was set, but the clock was not stopped for the ball to be set unless the previous play resulted in a stoppage of the clock. Now, the same intervals as the NFL are used, with minor differences for the final two minutes of each half. Various professional leagues have used their own standards ; the XFL, for instance, used a 35 - second play clock to encourage faster play. Also in the Canadian Football League, a time count is enforced differently at certain points of the game. If the time count occurs before the three - minute mark of a half, the penalty is five yards and the down is repeated. In the final three minutes, the penalty is a loss of down on first and second down or 10 yards, with the down repeated, on third down. If the referee deems a time count committed on third down in the last three minutes of a half to be deliberate, he also has the right to require the offensive team to put the ball in play legally within 20 seconds or else forfeit possession. ( Time counts during convert attempts, during which the ball is live but the clock does not run, are 5 - yard penalties with the down repeated at all times in the game. ) In the strategy of clock management, a team can slow the pace of a game by taking the maximum amount of time allotted between plays. A team wishing to do so would wait to snap the ball until there is one second left on the play clock. In many football games, the play clock is managed by the back judge who is positioned behind the defense and faces the quarterback. When the play clock counts down to 5 seconds remaining, some back judges will raise their arm over their head to warn the quarterback, and rotate their arm downward to their leg, counting down the final seconds. A penalty flag for delay is thrown afterward. The infraction typically results in a five - yard penalty. See also Pitch clock Shot clock References Jump up ^ For example, Electro - Mech, Eversan, Nevco, and other manufacturers call these devices `` delay of game timers '' in their literature. Jump up ^ `` NCAA Football Rules Committee Proposes Rules to Enhance Student - Athlete Safety and Encourage Consistent Pace of Play '' Jump up ^ `` Rule 1, Section 7, Article 9 -- Time Count '' ( PDF ). 2010 Canadian Football League Rule Book. Canadian Football League. p. 17. Retrieved November 18, 2010. 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Clock management Running out the clock Untimed play Garbage time Statistics Carry Completion Rushing yards Passing yards Passer rating Total quarterback rating Reception Receiving yards Pass deflected Sack Return yards Total offense Yards after catch Yards from scrimmage All - purpose yardage Touchdown pass Practice Two - a-days Oklahoma drill Three - cone drill Film session Officiating Official ( American, Canadian ) Chain crew Penalty Penalty flag Instant replay Miscellaneous Ball Coaching tree Concussions Equipment 12th man Letterman Overtime Running up the score Touchdown celebration Gatorade shower Tuck rule Uniform number Retrieved from `` https://en.wikipedia.org/w/index.php?title=Play_clock&oldid=824330083 '' Categories : American football terminology Canadian football terminology Hidden categories : Articles needing cleanup from July 2016 All pages needing cleanup Cleanup tagged articles with a reason field from July 2016 Wikipedia pages needing cleanup from July 2016 Talk About Wikipedia Add links This page was last edited on 6 February 2018, at 18 : 28. 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Question: when does the playclock start in the nfl
Answer: the end of the previous down