The I formation is one of the most common offensive formations in American football. The I formation draws its name from the vertical (as viewed from the opposing endzone) alignment of quarterback, fullback, and running back, particularly when contrasted with the same players' alignments in the T formation.

The formation begins with the usual 5 offensive linemen (2 offensive tackles, 2 guards, and a center), the quarterback under center, and two backs in-line behind the quarterback. The base variant adds a tight end to one side of the line and two wide receivers, one at each end of the line.

History

The exact origin of the I formation is unclear.Tom Nugent is credited with developing the I formation at Virginia Military Institute in 1950 as a replacement for the single-wing and an alternative to the T formation.Don Coryell, before popularizing Air Coryell, was also a pioneer of the I and used it as a high school coach in Hawaii, at Wenatchee Valley College in 1955, and at Whittier College in 1957-1959. In 1960, Coryell was an assistant coach under John McKay for the USC Trojans. By 1962, McKay's USC team won the national title with an offense built on the I.John Madden recalled going to an I formation clinic led by McKay. "We'd go to these clinics, and afterward, everyone would run up to talk to McKay," said Madden. "Coryell was there because he introduced [McKay]. I was thinking, 'If [McKay] learned from him, I'll go talk to [Coryell].' "