How many officials supervise a professional NFL game?

In American football, an official is a person who has responsibility in enforcing the rules and maintaining the order of the game.

During professional and most college football games, seven officials operate on the field. Beginning in 2015, Division I college football conferences are using eight game officials. College games outside the Division I level use six or seven officials. Arena football, high school football, and other levels of football have other officiating systems. High school football played under the National Federation of State High School Associations (NFHS) rules typically use five officials for varsity and 3, 4, or 5 for non-varsity games.

Football officials are commonly, but incorrectly, referred to as referees, but each position has specific duties and a specific name: referee, umpire, head linesman (or down judge), line judge, back judge, side judge, center judge (in Division I college football) and field judge. Because the referee is responsible for the general supervision of the game, the position is sometimes referred to as head referee or crew chief.