ZEROBASEONE (제로베이스원), also known as ZB1, is a South Korean boy group under WAKEONE known for being the winning group off the survival show BOYS PLANET. It currently consists of five members: SUNG HANBIN, KIM JIWOONG, SEOK MATTHEW, KIM TAERAE, and PARK GUNWOOK. Originally a nine-member lineup, ZHANG HAO, RICKY, KIM GYUVIN and HAN YUJIN left the group on March 15, 2026 following the group’s original contract expiration date.

The group’s nine-member lineup was finalized on April 20, 2023, upon the finale of BOYS PLANET, with their name refering to their “glorious beginning, starting from zero and ending with one.” They debuted on July 10, 2023, with “In Bloom,” the title track from their debut mini-album YOUTH IN THE SHADE. By selling over 1 million copies of it, they set a new record for a debut album—the first boy group to reach it since 1997.

The group’s second mini-album, MELTING POINT, was released on November 6, 2023, reaching again a huge commercial success.

Their lineup change in 2026 saw the group release Ascend-, an EP marking a sharp, sleek transition into contemporary R&B and a more “minimalist” sound.