The Arizona Cardinals are a professional American football team based in the Phoenix metropolitan area. The Cardinals compete in the National Football League (NFL) as a member of the National Football Conference (NFC) West division, and play their home games at State Farm Stadium in Glendale, a suburb northwest of Phoenix.

The team was established in Chicago in 1898 as the Morgan Athletic Club, and joined the NFL as a charter member on September 17, 1920. The Cardinals are the oldest continuously run professional football franchise in the United States, as well as one of only two NFL charter member franchises still in operation since the league's founding, the other also from Chicago, the Chicago Bears (the Green Bay Packers were an independent team and didn't join the NFL until a year after its creation in 1921). The team moved to St. Louis in 1960 and played there until 1987. The team in St. Louis was commonly referred to as the "Football Cardinals", the "Gridbirds" or the "Big Red" to avoid confusion with the Major League Baseball's (MLB) St. Louis Cardinals. Before the 1988 season, the team moved west to Tempe, Arizona, a suburb east of Phoenix and played their home games for the next 18 seasons at Sun Devil Stadium on the campus of Arizona State University. In 2006, the team moved to their current home field in suburban Glendale, although their executive offices and training facility remain in Tempe. From 1988 to 2012 (except 2005, when they trained in Prescott), the Cardinals conducted their annual summer training camp at Northern Arizona University in Flagstaff. The Cardinals moved their training camp to State Farm Stadium (then University of Phoenix Stadium) in 2013.

The Cardinals have won two NFL championships, both while the team were in Chicago. The first occurred in 1925, but is the subject of controversy, with supporters of the Pottsville Maroons believing that Pottsville should have won the title. Their second, and the first to be won in a championship game, came in 1947, nearly two decades before the first Super Bowl. They returned to the title game to defend in 1948, but lost the rematch 7–0 in a snowstorm in Philadelphia.

Since winning the championship in 1947, the team suffered many losing seasons, and currently holds the longest active championship drought of North American sports at 75 consecutive seasons. In 2012, the Cardinals became the first NFL franchise to lose 700 games since its inception. The team's all-time win–loss record (including regular season and playoff games) at the conclusion of the 2021 season is 584–787–41 (577–777–41 in the regular season, 7–10 in the playoffs). They have been to the playoffs eleven times and have won seven playoff games, three of which were victories during their run in the 2008–09 NFL playoffs. During that season, they won their only NFC Championship Game since the 1970 AFL–NFL merger, and reached Super Bowl XLIII in 2009, losing 27–23 to the Pittsburgh Steelers. The team has also won five division titles (1974, 1975, 2008, 2009 and 2015) since their 1947–48 NFL championship game appearances. The Cardinals are the only NFL team who have never lost a playoff game at home, with a 5–0 record: the 1947 NFL Championship Game, two postseason victories during the aforementioned 2008–09 NFL playoffs, one during the 2009–10 playoffs, and one during the 2015–16 playoffs.