View source for Playoffs

===National Football League===
{{Main|NFL playoffs}}

Evidence of playoffs in [[Professional football (gridiron)|professional football]] dates to at least 1919, when the "[[New York Pro Football League|New York Pro Championship]]" was held in [[Western New York]] (it is possible one was held in 1917, but that is not known for sure). The [[Buffalo, New York|Buffalo]] and [[Rochester, New York|Rochester]] metropolitan areas each played a final, the winners of which would advance to the "New York Pro Championship" on Thanksgiving weekend. The top New York teams were eventually absorbed into the [[National Football League]] upon its founding in 1920, but the league (mostly driven by an [[Ohio League]] that did not have true finals, though they frequently scheduled ''[[De facto|"de facto]]"'' championship matchups) did not adopt the New York league's playoff format, opting for a championship based on regular-season record for its first twelve seasons; as a result, four of the first six "championships" were disputed. Technically, a vote of league owners was all that was required to win a title, but the owners had a [[gentlemen's agreement]] to pledge votes based on a score (wins divided by the sum of wins and losses, with a few tiebreakers). When two teams tied at the top of the standings in 1932, an [[1932 NFL Playoff Game|impromptu playoff game]] was scheduled to settle the tie.

The NFL divided its teams into divisions in 1933 and began holding a single playoff final between division winners. In 1950 the NFL absorbed three teams from the rival [[All-America Football Conference]], and the former "divisions" were now called "conferences", echoing the college use of that term. In 1967, the NFL expanded and created four divisions under the two conferences, which led to the institution of a larger playoff tournament. After the 1970 [[AFL–NFL merger]] brought the [[American Football League]] into the NFL, the NFL began to use three divisions and a single wild-card team in each conference for its playoffs, in order to produce eight contenders out of six divisions; this was later expanded in 1978 and 1990 so that more wild-card teams could participate.

In 2002 the NFL added its 32nd team, the [[Houston Texans]], and significantly reshuffled its divisional alignment. The league went from 6 division winners and 6 wild-card spots to 8 division winners and only 4 wild-card qualifiers; by {{NFL year|2020}}, the number of wild-card qualifiers returned to six. The winners of each division automatically earn a playoff spot and a home game in their first rounds, the three top non-division winners from each conference also make the playoffs as wild-card teams. The division winner with the best record in the regular season gets a first-round bye, and each of the other division winners plays one of the three wild-card teams. In the divisional round, the lowest-seeded winner of a wild-card game then plays the lone bye team; the two wild-card winners also advance to play each other. The winners of these two games go to the conference championships, and the winners of those conference finals then face each other in the [[Super Bowl]].