The Big 12 Conference is a college athletic conference of ten schools located in the Central United States, with its headquarters located in Las Colinas, a community in the Dallas, Texas suburb of Irving. It is a member of the NCAA's Division I for all sports; its football teams compete in the Football Bowl Subdivision (FBS; formerly Division I-A), the higher of two levels of NCAA Division I football competition. Member schools are located in Iowa, Kansas, Missouri, Oklahoma and Texas, with a future member in West Virginia.

According to the Big 12 Conference's website, the alternate names "Big Twelve" and "Big XII" are incorrect. The trademarked name of the conference is Big 12 Conference, notwithstanding the Roman numeral XII featured on the conference logo.

The conference was officially formed on February 25, 1994, when four schools in Texas from the Southwest Conference joined the Big Eight Conference. Three months later, the schools decided to name the newly formed conference the Big 12 Conference. Athletic competition in the conference commenced on August 31, 1996. Although at the time of its formation the Big 12 was composed of the old Big Eight plus the four Texas schools, it regards itself as a separate conference, not an enlarged Big Eight, and it does not claim the Big Eight's history as its own. However, several college sports history sources consider both conferences as a single continuous operation dating to 1907.