NCT 127 is the second sub-unit of NCT. They made their debut as a seven member boy group on July 7, 2016 with the release of "Firetruck". The number 127 refers to the longitude for Seoul, where they are based. The group made a come back on January 6, 2017 with two new members, Johnny and Doyoung. On September 17, 2018, Jungwoo was announced as the unit's newest member ahead of their comeback.
All ten members of NCT 127 were originally part of SM Rookies, a pre-debut training team maintained by SM Entertainment. In January 2016, SM founder Lee Soo-man announced plans for a new boy group, with several different units to be based in cities around the world.
NCT 127 was officially announced on July 1, consisting of previously debuted NCT U members Taeyong, Taeil, Jaehyun, and Mark, along with three newly debuting members: Yuta, Winwin, and Haechan.
2016-2017: Debut, new members, Limitless and Cherry BombEdit
NCT 127 made their official debut with NCT #127 on July 10, 2016. The EP debuted at number two on the Gaon Album Chart, and topped the chart by the third week of its release. It also charted at number two on the Billboard World Albums Chart. Their debut performance took place on Mnet's M Countdown, where they played the lead single "Fire Truck" and "Once Again."
On December 6, NCT 127 released the music video for "Good Thing,” and on December 20, they released the music video for "Switch,” featuring members of the SM trainee group SR15B.
On December 27, SM Entertainment announced the addition of two new members to NCT 127: Johnny and NCT U's Doyoung.
2018: Empathy, Japanese debut, new member, Regular-Irregular, and RegulateEdit
On March 14, 2018, NCT 127 released the single "Touch” as part of NCT 2018 Empathy, a full-length studio album that brought together all active units of NCT, and grouped them under the collective name NCT 2018.
On May 23, NCT 127 released their Japanese debut EP Chain via Avex Trax. It peaked at number two on the Oricon Albums Chart.
In August 2018, it was announced NCT 127 will participate in the single "Let’s Shut Up and Dance," as part of a global collaborative tribute to Michael Jackson.
On October 12, NCT 127 released their first full-length album, Regular-Irregular, which debuted at number 86 on the US Billboard 200.The album also marked the addition of NCT U’s Jungwoo to the NCT 127 lineup, which now totals 10 members. The album release was led by a performance of English version of the lead single, "Regular" and "Cherry Bomb" on Jimmy Kimmel Live! which also marked the group's first appearance on U.S. national television.
On October 21, NCT 127 released a digital EP, Up Next Session: NCT 127, exclusively through Apple Music. It contains alternative versions of previous singles "Fire Truck," "Cherry Bomb," and "Regular," as well as an original track, “What We Talkin’ Bout”, which features Marteen.
On November 13, SM dropped teaser photos of the group, announcing the release of their first album repackage, Regulate, and new single, "Simon Says".
On November 22, SM has notified the general public that Winwin will not partake in promotions for Regulate, as he will be contributing in promotions for WayV.