Fun (stylized as fun.) is an American indie pop band based in New York City. It was formed by Nate Ruess, former lead singer of The Format, with Andrew Dost and Jack Antonoff, of Anathallo and Steel Train respectively. Fun has released two albums: Aim and Ignite in August 2009 and Some Nights in February 2012.

The band is best known for three hit singles from Some Nights: Grammy Award-winning "We Are Young" (featuring Janelle Monáe), "Some Nights", and "Carry On". "We Are Young" reached number one on the U.S. Billboard Hot 100 and Digital Songs charts. It also peaked at number one in the United Kingdom. "Some Nights" was released as the album's second single in June 2012, peaking at number three on the Hot 100 chart and becoming Fun's second Top 10 single, as well as the band's second song to reach platinum status in the United States.

On February 10, 2013, Fun won the Grammy Award for Best New Artist and the Grammy Award for Song of the Year for "We Are Young". Additionally, Fun was a nominee for four other Grammy Awards: Record of the Year and Best Pop Duo or Group Performance (both for "We Are Young") along with Album of the Year and Best Pop Vocal Album (both for Some Nights).