TO1 (Korean: 티오원; formerly known as TOO) (stylized in all caps) is a South Korean boy band formed by Mnet's 2019 reality show To Be World Klass. The group debuted on April 1, 2020, with their first mini album Reason For Being: Benevolence with "Magnolia" serving as the title track. Member Chihoon left the group on April 30, 2022, and members Minsu, Jerome, and Woonggi left the group on June 17, 2022, while Daigo, Renta, and Yeojeong were added to the group.