Cortis (; stylized in all caps) is a South Korean boy band formed by Big Hit Music. The group consists of five members: James, Juhoon, Martin, Seonghyeon, and Keonho.
Big Hit Music's third group after BTS and Tomorrow X Together, Cortis debuted on August 18, 2025 with the single "What You Want." They later released their first extended play, Color Outside the Lines, which debuted at number 15 on the Billboard 200, the secondâÂÂhighest entry for a KâÂÂpop act's debut album, and set records for firstâÂÂday sales, reached 200 million streams in record time for a rookie group, and surpassed two million in cumulative album sales.
They were the first Korean boy band to perform at a 2026 NBA All-Star Game, and won several accolades at the 10th Asia Artist Awards, 2025 MAMA Awards, and 40th Golden Disc Awards. They have been described as having a sound and image centered on authenticity and selfâÂÂexpression, and have been praised for redefining creativity within the KâÂÂpop industry.
The name "Cortis" is derived from six letters taken from the phrase "Color Outside the Lines.â According to the band's agency, the name "symbolizes the band's commitment to thinking freely, unconstrained by the norms and expectations set by society." The group announced their fandom name on Weverse as Coer (, pronounced as "core"), a blend of the group's name and the word "core," intended to signify fans as the group's support.
Prior to the formation of Cortis, most of the members had prior experience in entertainment, modeling, or music. James was a trainee with Big Hit's preâÂÂdebut group Trainee A from 2021 until the group's disbandment in 2022. He contributed to choreography and songwriting for other artists, working on tracks such as "Magnetic", "Cherish (My Love)", and "Tick-Tack" by Illit, and "Deja Vu" and "Miracle" by Tomorrow X Together. He also performed as a backing dancer for Jung Kook's live renditions of "Seven". Martin was a member of the Rainbow Children's Choir and served as a flag bearer for Iceland at the 2018 Winter Olympics before joining Big Hit a year later, also contributing to "Magnetic", "Deja Vu" and "Miracle" as a producer. Juhoon previously played soccer and worked as a child model, appearing in campaigns for various fashion brands and in music videos including VIXX's "Scientist," Zion.T's "Hello Tutorial" (with Ella Gross, later of Meovv), and MeloMance's "Tale," "You & I," and "Festival." Keonho was previously a competitive swimmer, noted for his skills and multiple victories at meets, before choosing to join Big Hit.
From April to May 2024, the members attended a song camp in Los Angeles, California, where they collaborated on the production of their debut album. In April 2025, Hybe, Big Hit's parent company, announced plans to debut a new boy band in the third quarter of 2025, with an August debut date confirmed in June. The group's members, Martin, James, Juhoon, Seonghyeon, and Keonho, were revealed on July 14, with the group's name disclosed on August 7.
On August 11, 2025, Cortis released their preâÂÂdebut single "Go!", with all members contributing to the songwriting and composition while the accompanying music video was filmed in Los Angeles. They officially debuted with the single "What You Want," featuring choreography performed on treadmills. Four days later, the group released an English version of the song featuring American singer Teezo Touchdown, and performed the track with him on Mnet's M Countdown. They released a trailer for their documentary What We Want on August 30, which documented the production of their debut album in Los Angeles, with the first episode being released on September 1. They released their debut EP, Color Outside the Lines, on September 8, accompanied by the single "Fashion". The music video, filmed in Christchurch, New Zealand, accumulated one million views within 12 hours. Their EP sold approximately 250,000 copies on its first day, setting a new record for firstâÂÂday sales by a KâÂÂpop act that debuted in 2025.
By November, Color Outside the Lines had surpassed 200 million streams on Spotify, the fastest for a KâÂÂpop rookie debuting that year to reach the milestone. In December 2025, Cortis were announced as headliners for the NBA Crossover concert series in February 2026, alongside Ludacris and Shaboozey. That same month, they performed at Tokyo National Stadium for KBS2's 2025 Music Bank Global Festival in Japan, performing "What You Want" and a cover of BTS's "Mic Drop." By the end of the year, Cortis won multiple awards, including Rookie of the Year and Best Performance at the 10th Asia Artist Awards, and Best New Artist at the 2025 MAMA Awards.
In January 2026, Cortis attended the 40th Golden Disc Awards, where they won Rookie Artist of the Year alongside coâÂÂed group AllDay Project, and was later nominated for Best KâÂÂpop New Artist at the 2026 iHeartRadio Music Awards while "Go!" was nominated for Favorite TikTok Dance. They were named Friends of the NBA to help promote the league in Asia and were announced as the headlining performers for the 2026 NBA All-Star Game, becoming the first KâÂÂpop group to perform at the event.
They headlined the NBA Crossover Concert Series at the Los Angeles Convention Center on February 12, 2026, and released the song "Mention Me" the following day as part of the soundtrack for the American animated film Goat. During the concert, they performed a new song titled "Young Creator Crew (YCC)" as a teaser for their upcoming second EP, with the track being heavily promoted on their TikTok. They performed at the Kia Forum during halftime of the 2026 NBA All-Star Celebrity Game, becoming the first KâÂÂpop group to headline a halftime show in the event's history.
On March 6, 2026, Cortis announced their second EP, GreenGreen, set for release on May 4, with the title track scheduled to release on April 20. On the same day, Color Outside the Lines surpassed two million sales, becoming the second KâÂÂpop group to reach that milestone with a debut album after Zerobaseone. They announced the title track from GreenGreen as "RedRed" on March 30, 2026, with GreenGreen having accumulated over 565,000 preâÂÂsaves on Spotify.
Cortis have cited hip hop as an influence while emphasizing a musical identity centered on authenticity and selfâÂÂexpression. Other Western genres have also influenced the group, with Forbes noting that Cortis sounded "more westernized or global than most rookie groups," while the members still identify as K-pop artists. Martin, the group's leader, cites Tyler, the Creator and Mac Miller among his favorite artists. Each member contributes to the group's dynamic, which Rolling Stone characterized as "curious about the future, wanting the whole world to know their names." Their styling, led by creative director Seoyoung Kim and Actoy, draws on punk and Y2K aesthetics. Teen Vogue praised the look as "spearheading the Y2K menswear renaissance," noting its skate-punk-inspired aesthetics. They were described as a "young creator crew" for their involvement in music, choreography, and video production.
The Hollywood Reporter observed that although songs such as "Go!" and "What You Want" were sonically different, both suited the groupâÂÂs artistic vision, concluding that "Cortis seems focused on one thing more than making exactly the kind of music expected of them: authenticity." The group's musical identity and social media content were described by The Korea Herald as creating "a distinct identity for themselves through fresh sounds and performances that defy expectations." The publication cited them, alongside More Vision boy band Lngshot, as among the acts redefining creativity within the industry. Color Outside the Lines was included on the list of the 15 Best NonâÂÂEnglish Albums of 2025 by Teen Vogue, with the publication describing the record as "short and slightly derivative of their influences" but noted it "stands as a testament to what's to come."