What is the Red Zone in Football?
The red zone in football is the area of the field from each 20 yard line to the nearest goal line. Each team's red zone is from the 20 yard line to the goal line on their opponent's side of the field. When an offense enters the red zone, they have a high probability of scoring the football as they are only 20 yards from a touchdown and the longest possible field goal in the red zone is 37 yards. A teams efficiency in the red zone is measured by a teams red zone percentage which is calculated by the equation (times scored in red zone / times entered the red zone).
Red Zone Advantages
For the defense, it is very difficult to stop the opposing offense once they enter the red zone. There is very little space to work in and can severely limit a defense on playcalling. The same is true for the offense, with the limited space requiring for more creative playing call and improvising from the receiver in order to get open for a pass.
Strategies for both the offense and defense change dramatically when a team is in the Red Zone, with both teams generally opting for more conservative play calling. While the offense ideally wants to score a touchdown and earn six points, the quarterback must be careful not to throw an interception on a passing play to avoid losing out on an easy field goal for the kicker should a touchdown not be scored, as three points is much preferred to losing possession of the ball.
The team playing defense is likely to be more conservative as well, dropping more players into coverage rather than pressuring the quarterback in order to force the offense to settle for a field goal rather than leaving a player open for an easy touchdown.