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아이오아이

Girl group · YMC Entertainment and CJ E&M (2016-2017); Swing Entertainment for the 2026 reunion · since 2016

I.O.I

아이오아이

Eleven trainees from different agencies, voted together on Produce 101 for a group meant to last a year. Nine of them came back in 2026, and "Suddenly" went to No. 1 on Melon.

11years on 4 May 2027 · in 191 days

Their story

Picked by the public

I.O.I came out of Mnet's Produce 101 in 2016, where 101 trainees from different agencies competed and viewers decided who stayed. In April the final eleven were set, with JYP trainee Jeon Somi at the top of the vote. The plan was fixed from the start: about ten months of releases and shows, then everyone back to their own company. Nayoung was voted leader by the members, and Chrysalis, led by the hopeful "Dream Girls", followed in May.

Very Very Very

The summer belonged to a unit. Seven members released the brassy "Whatta Man", which gave I.O.I their first music show trophy. In October all eleven returned with "Very Very Very", a gift song from Park Jin-young, and it became their first No. 1. By the end of the year they had the rookie prize at MAMA. The goodbye came on schedule: the single "Downpour" in January 2017 and three farewell nights at Jangchung Gymnasium.

A group of soloists

Because the members kept their own agencies, I.O.I always sounded like eleven careers meeting in one place. Several of them were also in other groups, from DIA to gugudan. The songs moved between bright girl group pop and ballads, and a decade later the members wrote much of the music themselves. On I.O.I : LOOP Somi, Yeonjung and Chungha all have writing credits, and "Goodbye with a Smile", recorded in 2016, finally got its release.

Where they are now

In February Swing Entertainment announced a reunion for the tenth anniversary in 2026. Nine members took part; Mina and Jieqiong stayed out because of other commitments. The fandom finally got an official name, Angdungi. "Suddenly" came out in May, topped Melon and was still collecting music show trophies in July. After Seoul, the LOOP tour went to Bangkok and Hong Kong. The tour closed the anniversary project. Accepting the last trophy in July, Yoojung only joked that they might suddenly turn up again someday.

Timeline

  1. Debut with Chrysalis and "Dream Girls".

  2. All eleven return with "Very Very Very", their first No. 1 hit.

  3. Final single "Downpour" and the farewell concert Time Slip.

  4. Swing Entertainment announces a nine-member reunion for the 10th anniversary.

  5. "Suddenly" is still winning music shows as the anniversary project ends.

  6. 25 October 2026

Start with these 5 songs

  1. Dream GirlsThe debut title track, about dreams that pay off.2016
  2. Whatta ManThe seven-member unit single that brought the first trophy.2016
  3. Very Very VeryProduced by Park Jin-young and their first No. 1.2016
  4. DownpourThe goodbye single, No. 1 on eight Korean charts on release day.2017
  5. SuddenlyThe synth-pop reunion single, with lyrics co-written by Somi.2026

In the Fan Chart

The Fan Chart on The Crowd adds up every fan's top 10. Here is where I.O.I stands.

    Add I.O.I to your setlist

    For Angdungi

    NayoungLeader

    임나영
    Name
    Im Na-young

    Chosen as leader by a vote of all eleven members.

    Chungha

    Wrote and composed the ballad "Back Then, Us Now" on I.O.I : LOOP.

    Sejeong

    김세정
    Name
    Kim Se-jeong

    Came second in the Produce 101 vote and was a Jellyfish trainee.

    Chaeyeon

    정채연
    Name
    Jung Chae-yeon

    Was also a member of DIA at MBK Entertainment during the I.O.I year.

    Jieqiong

    주결경
    Name
    Zhou Jieqiong

    In the "Whatta Man" unit; sat out the 2026 reunion because of other plans.

    Sohye

    김소혜
    Name
    Kim So-hye

    One of the seven in the 2016 "Whatta Man" sub-unit.

    Yeonjung

    유연정
    Name
    Yoo Yeon-jung

    Wrote the rock-based track "IF I" on the 2026 album.

    Yoojung

    최유정
    Name
    Choi Yoo-jung

    Came third in the final vote, as a Fantagio trainee.

    Mina

    강미나
    Name
    Kang Mi-na

    Also in gugudan at Jellyfish; could not join the 2026 reunion because of her schedule.

    Doyeon

    김도연
    Name
    Kim Do-yeon

    Part of the 2016 sub-unit that sang "Whatta Man".

    Somi

    전소미
    Name
    Jeon So-mi

    Won the Produce 101 vote with 858,000 votes; wrote "IOI (Where My Girls At)" in 2026.

    Quick answers

    When did I.O.I debut?

    On 4 May 2016, with the EP Chrysalis and the title track "Dream Girls".

    Who are the members of I.O.I?

    Nayoung (leader), Chungha, Sejeong, Chaeyeon, Jieqiong, Sohye, Yeonjung, Yoojung, Mina, Doyeon and Somi. Mina and Jieqiong did not take part in the 2026 reunion because of prior commitments.

    What is the I.O.I fandom called?

    Angdungi (앙둥이), made official in April 2026. It recalls the nickname the members used for their fans in 2016.

    How were the members chosen?

    By viewer votes on Mnet's Produce 101 in 2016. Out of 101 trainees from different agencies, the top 11 became I.O.I; Jeon Somi received the most votes.

    Are I.O.I still together?

    Not as a permanent group. The original activities ended with a final concert in January 2017. Nine members returned for the 10th anniversary in 2026 with I.O.I : LOOP and an Asia tour, and that project wrapped up in July 2026.

    Know your I.O.I?Six K-pop questions a day in the Daily, and a collectible card for every finished set.

    Play the Daily

    Last checked 24 October 2026. Sources include The Korea Times, Newsis, Sports Khan, SBS Star and Soompi. Spotted a mistake? Tell us.