Reputation, Taylor Swift's sixth studio album, was released on Friday, November 10, 2017, through Big Machine Records, when Swift was 27. It followed nearly three years after 1989 and a period in which Swift largely withdrew from public view, and its songs moved toward darker electronic pop while addressing media scrutiny, privacy and a new relationship.

The lead single, "Look What You Made Me Do," was released in August 2017 and reached No. 1 on the Billboard Hot 100. Swift chose not to give interviews to promote the album, and she performed "New Year's Day" on The Tonight Show Starring Jimmy Fallon in the week of its release.

The album sold more than a million copies in its first week in the United States, the fourth Swift album to do so after Speak Now, Red and 1989. According to Billboard, she became the only artist with four million selling weeks since Nielsen began electronic tracking in 1991, and Reputation was the first album to reach that mark since Adele's 25 in 2015. It became the biggest album debut of 2017 in the United States.

Shortly after the album's release, Swift announced the first leg of a stadium tour. On May 8, 2018, she opened the Reputation Stadium Tour at State Farm Stadium in Glendale, Arizona, the same stadium where she would launch the Eras Tour five years later. The tour played stadiums across North America, Europe, Oceania and Asia through November 2018, and it was later released as a concert film on Netflix on December 31, 2018. During a tour stop in Pennsylvania, Swift visited Pine Ridge Farm, the Christmas tree farm where she spent her early childhood, told in Childhood Home.

Reputation was the last album Swift released under her contract with Big Machine. In November 2018 she signed with Republic Records and Universal Music Group, and seven months later the sale of Big Machine to Scooter Braun's Ithaca Holdings put the masters of Reputation and her five earlier albums in his company's hands, the dispute told in Battle of Masters. Reputation had not been rerecorded when Swift bought back her original masters in May 2025.