Jack Antonoff is a singer, songwriter, and record producer best known as the lead guitarist of the indie rock band Fun. He was previously the lead singer-songwriter of the band Steel Train and currently holds that role in indie-pop outfit Bleachers.

Jack Antonoff was born in Bergenfield, New Jersey, and is the younger brother of fashion designer Rachel Antonoff. During his sophomore year of high school, he and several friends from elementary school formed a punk rock band, Outline; the band was successful enough to tour in Florida and Texas.

The band disbanded after several members left to attend college. In 2002, Antonoff and his friend Scott Irby-Ranniar formed a new band, Steel Train, and secured a recording deal with Drive-Thru Records.

Antonoff would be the new group's lead singer. They soon recruited drummer Matthias Gruber and then convinced one of their friends from the band Random Task, Evan Winiker, to drop out of college to join the new band.

In 2008, Nate Ruess (formerly the frontman of The Format) asked Antonoff to join him and Andrew Dost (formerly of Anathallo) in a new band, which became Fun. Antonoff was already well acquainted with Ruess and Dost because their former bands had all toured together.

Fun's second album Some Nights saw the band score its first #1 hit single, "We Are Young," which Antonoff co-wrote with Ruess, Dost, and Jeff Bhasker. Aside from his work with Bleachers and Fun, Antonoff has worked as a songwriter and record producer with various artists, including Taylor Swift, Lorde, St.

Vincent, Lana Del Rey, Kevin Abstract, Carly Rae Jepsen, and Troye Sivan. Antonoff has been nominated for a Golden Globe Award and has won several Grammy Awards: two for his work with Fun, one for production on Taylor Swift's album 1989, and one with St.

Vincent for writing the title track on Masseduction. He also started his own music festival, Shadow of The City, which takes place annually in New Jersey.