X1

Boy band X1 debuted in August 2019 under Stone Music Entertainment and Swing Entertainment with the EP "Quantum Leap." It was formed in July 2019 with the top 11 finalists of Mnet's hit audition program "Produce X 101," the fourth and final season of the "Produce" franchise.

It consisted of members Kim Yo-han, Kim Woo-seok, Han Seung-woo, Song Hyeong-jun, Cho Seung-youn, Son Dong-pyo, Lee Han-gyul, Nam Do-hyon, Cha Jun-ho, Kang Min-hee and Lee Eun-sang.

The group's name means that an unknown number (X) of idol hopefuls become one. X was also a key term on the audition show.

With the show's popularity, X1 had a sensational debut, selling over 524,000 copies of its debut EP. It was the first K-pop album by a debuting artist to sell more than half a million copies and still holds the title of highest CD sales by a debuting K-pop act. The group was originally meant to be a temporary project group active for five years — the longest for any project group formed by the "Produce" franchise. However, the boy band disbanded prematurely in January 2020 — after only releasing its debut album — after the producers of the "Produce" series were accused of and later convicted for manipulating the shows' votes and rigging the list of finalists.

The group's fandom is dubbed One It.

Where are X1 members now?

Kim Yo-han debuted as a member of the boy band WEi in 2020 and is also an actor.

Kim Woo-seok is a solo singer and actor.

Cho Seung-youn is a solo singer and rapper, also known as Woodz.

Kang Min-hee and Song Hyeong-jun debuted as members of the boy band Cravity in 2020.

Cha Jun-ho debuted as a member of the boy band Drippin in 2020.

Lee Han-gyul and Nam Do-hyon debuted as members of the boy band BAE173 in 2020. Nam, who has been on hiatus since October 2022 due to health issues, left the band on June 22, 2023 and terminated his exclusive contract with his agency Pocket Doll Studio. Nam said while no detailed plans about his future activities have been confirmed, he promised to “return with improvements, as musician Nam Do-hyon.”

Son Dong-pyo debuted as a member of the boy band Mirae in 2021.

Han Seung-woo returned to his original group Victon, which debuted in 2016 and is still active.

Lee Eun-sang launched his solo music career in 2020 and went on to debut as a member of the boy band Younite in 2022.