Stage Name: Jaehyun (재현)
Birth Name: Jeong Jae-hyun
Legalized Name: Jeong Yun-oh 
Birth Date: February 14, 1997
Height: 180 cm
Weight: 63 kg
Blood Type: A

Jaehyun was born on February 14, 1997, in Seoul, South Korea. He studied abroad in Connecticut, USA for four years. He was scouted by SM outside of his school in 2012, while he was on clean up duty. He auditioned with the song “Mama” by EXO and was accepted as a trainee. 

On December 9, 2013, Jaehyun was introduced as a member of the pre-debut trainee group SMROOKIES. In 2014, he along side with his members joined the show “EXO 90:2014”, where they performed K-pop songs from the 90s. From January to July, 2015, he along side with Doyoung were MCs for Show Champion. In July 2015, he along side with Ten competed in “Hope Basketball All-star”. Jaehyun performed “A Whole New World” for Disney Channel Korea’s The Mickey Mouse Club on December 2015. 

In April 2016, Jaehyun made his official debut as a member of NCT, in the first sub-unit NCT United, with the singles ‘The 7th Sense” and “Without You”. On July 10m he debuted as a member of the second sub-united, NCT 127, with their first extended play, NCT #127. In March 2017, Jaehyun became a radio DJ along with member Johnny for NCT Night Night. In November 2017, he and d.ear released the single, “Try Again” for SM Station. In December, he was featured in the music video for Wendy and Baek A-yeon’s single, “The Little Match Girl”. In January 2018, Jaehyun rejoins NCT U with the release of “Timeless” for SM Station project. 

In October 2019, Jaehyun became an MC for SBS’ Inkigayo, hosting the show weekly every Sunday. On September 2020, it was announced that Jaehyun will make his acting debut in the upcoming KBS2 drama Dear.M, which is set to release in 2021, with the leading role of Cha Min-ho, a college student majoring in Computer Science.