American Gridiron football, though Rugby League and Rugby Union (two other forms of football) use similar length fields/pitches. An Association Football pitch is almost always longer than a Gridiron field, depending on how you measure (it is typical to exclude the end-zones when measuring a Gridiron field, and while Rugby and Gridiron football have a playable area behind the goal (or try) line, Association Football does not.
As a side-note Canadian Gridiron football uses a longer field than American Gridiron football, though (measuring between the goal lines) still slightly shorter than a typical Association Football pitch.
Australian Rules Football is on a field typically longer even than an Association Football pitch, though I don't believe there is a regulation limiting the size.
American Gridiron football, though Rugby League and Rugby Union (two other forms of football) use similar length fields/pitches. An Association Football pitch is almost always longer than a Gridiron field, depending on how you measure (it is typical to exclude the end-zones when measuring a Gridiron field, and while Rugby and Gridiron football have a playable area behind the goal (or try) line, Association Football does not.
As a side-note Canadian Gridiron football uses a longer field than American Gridiron football, though (measuring between the goal lines) still slightly shorter than a typical Association Football pitch.
Australian Rules Football is on a field typically longer even than an Association Football pitch, though I don't believe there is a regulation limiting the size.