H1-KEY (하이키) is a South Korean girl group under Grandline Group (GLG) entertainment. The group consists of four members: Seoi, Riina, Hwiseo and Yel. Former member Sitala left due to personal reasons. The fandom name is M1-KEY.

H1-KEY made their debut January 5th, 2022 with the single-album Athletic Girl. In 2023 the group released their album Rose Blossom, which spawned the sleeper hit “건물 사이에 피어난 장미 (Rose Blossom).” The song was co-written by DAY6 member Young K and climbed the charts thanks to its lyrical message of empowerment.

The group kicked off 2024 with the English single “Thinkin' About You,” which is part of their new project dubbed as H1-KEYnote.

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