The size of an American football field is 360 by 160 feet. That is 109.7 by 48.8 meters or 120.0 by 53.3 yards. There are long and short boundary lines. The longer ones are sidelines and the shorter ones are the end lines. Both are considered out of bounds.
The goal lines are located at the end of each field. The goals are 100 yards (91.4 m) distant from each other. The end zone is the scoring section. It goes 10 yards (9.1 m) beyond the goal line up to the end line.
The goal line is included in the end zone but not the end line. The playing field is relatively flat. The middle area is a bit higher so water drains easily.
Yard Lines and Hash Marks
The yard lines traverse the field every 4.6 meters (5 yards). The numbering of the yard lines is every 10 yards beginning at the goal line. It goes up to the midfield or 50 yard line. This is akin to the system used in rugby league field.
The hash marks or inbounds lines run at 1-yard (91.4 cm) intervals. These are at right angles to the sidelines. Given the size of an American football field, it means all the plays begin at these hash marks. The field is sometimes called gridiron owing to its appearance.
The goalposts or uprights are linked to a crossbar 10 feet (3.05 m) high from the ground. The width varies. For low skill levels it is 23 feet 4 inches (7.11 m). For higher skill sets it is 18 feet 6 inches (5.64 m).
The typical American football game is made up of four quarters. Each is 15 minutes long. In high school football, each quarter is 12 minutes long. There is a 12 break after the second quarter. In reality, the game lasts much longer.
Some plays cause the game clock to stop. Televised games have breaks to air commercials. The game can last for three hours especially if it is televised. Extra time for play is given if both teams end up tied after four quarters. The first team to score a touchdown in the extra period wins.
The size of an American football field is sometimes used in other leagues outside the US. But other federations may use different figures. College and high school football games have variations in the measurements too.