The rectangular field of play used for American football games measures 100 yards (91.44 m) long between the goal lines, and 160 feet (48.8 m) (53+1⁄3 yards) wide. The field is made of grass. In addition, there are end zones extending another 10 yards (9.144 m) past the goal lines to the "end lines", for a total length of 120 yards (109.7 m).

When the "football field" is used as unit of measurement, it is usually understood to mean 100 yards (91.44 m), although technically the full length of the official field, including the end zones, is 120 yards (109.7 m).

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