Group profile and current lineup

THE NATION’S PICK · ELEVEN FOREVER

I.O.I

Disbanded girl group · 2016–2017 · reunion 2026

Eleven women, one temporary contract, nine years of unfinished emotional business, and a reunion that remembered the difference between “not promoting” and “not a member.”

I.O.I was designed to end. That was the contract. The fact that they returned anyway, with adult careers, member-written songs and enough history to make one denim-and-white-shirt formation emotionally dangerous, is exactly why the reunion hits.

RaeRae take:

Meet all eleven members

The 2026 anniversary promotion used nine members. The group still has eleven. Kang Mina and Zhou Jieqiong had prior commitments. They were not erased, replaced or quietly voted off the family group chat.

Lim Nayoung

Leader · rapper · dancer · vocalist

The “Stone Nayoung” who looked unshakeable, then spent the reunion proving the stone had feelings after all.

Chungha

Main dancer · lead vocalist

The member who turned an I.O.I dance break into one of K-pop’s strongest solo careers.

Kim Sejeong

Main vocalist

Produce 101’s vocal and variety powerhouse, now equally recognizable as an actor and solo singer.

Jung Chaeyeon

Vocalist · visual

DIA member turned established actor, with the face that helped define the first season’s visual conversation.

Zhou Jieqiong

Dancer · vocalist · visual

Original member. Active primarily in China and unable to join the 2026 promotion. Still I.O.I.

Kim Sohye

Vocalist · actress

The acting trainee whose improvement arc became the show’s most debated proof that potential can be part of a vote.

Yoo Yeonjung

Main vocalist

The eleventh-place finale shock who became essential the moment a chorus needed actual lift.

Choi Yoojung

Rapper · dancer · vocalist

The original “Pick Me” center whose stage personality could survive being surrounded by one hundred other trainees.

Kang Mina

Dancer · rapper · vocalist

Original member. Acting commitments kept her from the 2026 promotion. Still I.O.I.

Kim Doyeon

Dancer · vocalist · visual

From I.O.I and Weki Meki to acting and fashion, with a stage frame built for cameras that know how to use it.

Jeon Somi

Center · vocalist · dancer

The first-place center who survived SIXTEEN, won Produce 101 and eventually built a solo identity large enough to escape both shows.

Quick file

Debut: May 4, 2016

Origin: Produce 101, season one

Original lineup: 11 members

Original run ended: January 2017

10th anniversary reunion: May 2026

Fandom: U&I

Original management: YMC Entertainment / CJ E&M

2026 management: Swing Entertainment

What the name means

I.O.I stands for “Ideal of Idol” and visually echoes 101, the show that formed them.

The name now carries a second meaning the producers probably did not plan: the basic introductory course for every K-pop project group that came afterward.

Why I.O.I matters more than one nostalgic comeback

I.O.I proved that viewers would emotionally adopt trainees from competing agencies, finance a temporary group and continue following the members after the contract expired. Wanna One, IZ*ONE, X1, Kep1er, ZEROBASEONE and the larger ecosystem of idol assembly shows all inherited pieces of that model.

The experiment worked because the ending was visible from the beginning. Fans were not only voting for a debut. They were watching an expiration date approach. That created urgency, spending and attachment. It also taught the industry that planned grief could be part of a marketing strategy, which is a sentence I hate because it is true.

I.O.I was not disposable just because the contract was temporary. The agencies treated the calendar like the group’s defining fact. Fans treated the relationships and music as the defining fact. Nine years later, the fans won that argument.

My verdict:

Produce 101 changed the audience’s job

The first season gathered 101 female trainees from multiple companies and called viewers “national producers.” Voting made the audience feel responsible for the final eleven. Weekly rankings turned training progress, editing and personality into public data.

That participation was powerful and dangerous. A strong edit could rescue a trainee. A bad one could flatten a person into one mistake. Skill mattered, but so did screen time, narrative and whether the producers decided someone’s tears belonged before or after the commercial break.

Later Produce seasons became inseparable from vote-manipulation crimes. I.O.I’s final lineup was not overturned by those later court cases, but the franchise they launched eventually demonstrated the problem with asking audiences to trust a television company that profits from both the competition and the result.

The original run barely had time to breathe

April 2016: the Produce 101 finale selected Somi, Sejeong, Yoojung, Chungha, Sohye, Jieqiong, Chaeyeon, Doyeon, Mina, Nayoung and Yeonjung.

May 2016: Chrysalis and “Dream Girls” launched the full group. The debut had enormous attention and an identity that still felt assembled from several companies’ ideas.

August 2016: a seven-member unit released “Whatta Man.” Sejeong, Chaeyeon, Yeonjung and Mina were unavailable because their original agencies had pulled them into other activities. Yes, I.O.I had schedule fragmentation before the group had existed for four months.

October 2016: all eleven returned for miss me? and “Very Very Very,” the song that most cleanly converted their chaotic charm into one bright, relentless hook.

January 2017: “Downpour,” written by SEVENTEEN’s Woozi and collaborators, closed the contract period. The farewell concert turned a project-group clause into public mourning.

The agency problem was baked into the design

Each member still belonged to an original company with separate plans. Some agencies wanted to capitalize on Produce attention immediately. Sejeong and Mina debuted in gugudan while I.O.I was active. Chaeyeon returned to DIA. Yeonjung joined WJSN. That overlap did not mean the women lacked loyalty. It meant the project had never fully controlled the calendar.

The short-term rush also scattered momentum. PRISTIN, Weki Meki and gugudan contained popular I.O.I members but did not receive equal long-term support or success. Chungha and Somi built solo careers. Sejeong expanded through music and acting. Sohye committed to acting. Several members proved I.O.I had identified valuable artists. Their companies did not always prove they knew what to do next.

Current song: “Suddenly”

Read RaeRae’s complete “Suddenly” reaction

“Suddenly” does not pretend nine years vanished. It uses adult voices, old visual language and the strange intimacy of watching people return to a place they were never allowed to keep.

The 2026 reunion did not rewrite the membership

Nine members participated in I.O.I : LOOP: Nayoung, Chungha, Sejeong, Chaeyeon, Sohye, Yeonjung, Yoojung, Doyeon and Somi. Mina and Jieqiong could not join because of prior commitments. That makes the promotion OT9. It does not retroactively make I.O.I a nine-member group.

On May 4, the anniversary project released “Goodbye With A Smile,” an archival track recorded in 2016 with all eleven voices. The new mini album followed with “Suddenly” and material that allowed members to participate as adults rather than recreate school-uniform innocence.

The official reunion content later closed its chat service in July 2026, reinforcing that this was a defined anniversary project rather than a quiet permanent relaunch. Temporary again. Disposable still no.

Where all eleven careers went

Solo music

Chungha and Somi became major soloists. Sejeong built a solo catalog alongside acting. Yeonjung continued as a primary WJSN vocalist and musical performer.

Acting

Sejeong, Chaeyeon, Sohye, Mina, Doyeon and Nayoung developed substantial acting careers. The “idol actress” label covers very different levels of training and success, so their individual pages break those careers apart properly.

Post-I.O.I groups

PRISTIN, gugudan, Weki Meki, DIA and WJSN received different outcomes. Some flourished, some ended too early, and some became examples of how survival-show fame cannot repair weak company planning.

China

Jieqiong developed music, acting and television work in China. Her physical absence from the 2026 Korean schedule does not erase the career she built or the group she debuted in.

Performance and variety

Yoojung’s all-round skill, Nayoung’s leadership and the members’ variety chemistry were central to I.O.I even when those contributions were harder to measure than chart positions.

The network survived

The reunion was possible because the members continued treating I.O.I as a relationship, not an embarrassing trainee-era job they had outgrown.

Essential discography

Year — Release · Why it matters

2016 — Chrysalis“Dream Girls” · “Crush” · The public introduction. Uneven, earnest and permanently attached to the shock of seeing the final eleven together.

2016 — Whatta Man · The seven-member unit found a harder performance identity and gave Chungha’s choreography power room to breathe.

2016 — miss me?“Very Very Very” · “Hold On” · The best full-group pop package from the original run.

2017 — “Downpour” · A farewell ballad that understood fans did not need another dance break. They needed permission to cry.

2026 — I.O.I : LOOP · “Suddenly,” “SPF 100+,” “IF I,” “Then, Now and Forever” and the archival OT11 “Goodbye With A Smile.”

Start here if you missed 2016

1. “Very Very Very” for the full-group hook and the sound most people remember first.
2. “Whatta Man” for the unit’s harder performance lane.
3. “Downpour” when you are emotionally prepared to understand why the disbandment still hurts.
4. “Suddenly” for the adult reunion and the sound of a promise finally collecting interest.
5. Produce 101’s “Pick Me” stage to see the cultural starting gun, giant pyramid and all.

Tea, receipts and recurring reunion rumors

I.O.I reunion plans circulated repeatedly before 2026. A 2019 attempt was delayed and eventually collapsed amid scheduling problems and the broader Produce scandal. The 2021 anniversary livestream kept the emotional door open without pretending a comeback was already signed.

The useful lesson is simple: a member saying “we want to reunite” is sincere, but it is not a release announcement. Eleven careers, agencies, countries and calendars must agree. The 2026 project mattered because desire finally became contracts, recordings and a stage.

Official links and receipts

10th anniversary Instagram

10th anniversary X

TikTok

b.stage

“Suddenly” MV

Sources and further reading

• The Korea Times: I.O.I’s return after nine years
• The Korea Times: why the I.O.I reunion means more than nostalgia
• StarNews: the 10th anniversary project and nine participating members
• The Korea Times archive: the 2016 final mini album
• Soompi: reunion rollout timeline
• SBS: I.O.I : LOOP report

The reunion changed the answer, not the history

BLUF: I.O.I is no longer a group that can be filed only under “gone too soon.” The 2026 LOOP project gave nine members a real comeback, a six-song EP and an anniversary tour without pretending the original eleven-member story had been erased. Kang Mina and Zhou Jieqiong did not participate in this cycle; that is a participation note, not permission to edit them out of the group’s history. Accuracy is less dramatic than fandom arithmetic, but it ages much better.

LOOP also fixes a lazy assumption about project groups: expiration does not make the relationships disposable. The original run lasted months, yet the audience carried “Very Very Very,” “Whatta Man” and “Downpour” for a decade. “Suddenly” works because the grown women are not cosplaying their 2016 selves. The song lets memory sit beside adulthood, then asks whether a temporary group can become a recurring home.

For new listeners, start with “Dream Girls” to hear the earnest launch, “Whatta Man” for the unit’s harder silhouette, “Very Very Very” for pop-engine precision, “Downpour” for the goodbye, and “Suddenly” for the return. That sequence explains I.O.I better than a ranking ever could: possibility, adaptation, peak, grief, and finally a reunion with enough life in it to be more than a commemorative photo.

React image cards

Static cards route each exact official upload to its own in-depth React. Every card repeats that React’s featured and hero image so the archive stays visually traceable.

Suddenly

Exact-video React · Read the full review

The reunion happened: the 2026 file

I.O.I did not remain a beautiful maybe. Swing Entertainment confirmed a tenth-anniversary comeback, nine members released the mini album I.O.I : LOOP on May 19, 2026, and the group followed it with concerts in Seoul, Bangkok and Hong Kong. After nine years, the project-group promise finally received an adult answer instead of another interview quote about schedules.

The participating lineup was Lim Nayoung, Chungha, Kim Sejeong, Jung Chaeyeon, Kim Sohye, Yoo Yeonjung, Choi Yoojung, Kim Doyeon and Jeon Somi. Kang Mina and Zhou Jieqiong could not join because of prior schedules. That is an anniversary-project participation fact, not an official statement deleting them from I.O.I’s original eleven-member history.

The Seoul run filled Jamsil Indoor Stadium for three dates from May 29 through 31. Bangkok followed, then Hong Kong on June 20 and 21. The tour mattered because reunion nostalgia can be faked in a single television edit; a concert requires the songs, formations, stamina and relationships to survive a full room again.

Suddenly was the correct comeback argument

“Suddenly” did not try to convince listeners that 2016 had been preserved in a freezer. The members returned with separate careers, different vocal weights and nine years of public life between them. The song uses that distance as material rather than dressing everybody in a first-era costume and shouting ‘remember this?’ until emotion appears.

The exact official MV `Jxgbfc89hNI` has its own Iconic-by-Mistake React, local canonical image and release-date relationship. It belongs to the nine participating members. Mina and Jieqiong remain connected to the group hub and original catalog but do not inherit a video they did not perform in.

That participation rule is the difference between an archive and a fandom mood board. Loving all eleven does not require falsifying the nine onstage. Both truths fit: I.O.I is an eleven-member historical group, and the 2026 reunion project was performed by nine.

The album had to connect eleven histories without pretending they matched

By 2026, the members had become solo singers, group members, actors, musical performers, television personalities and cross-border artists. A reunion album could not treat those paths as inconvenient side quests before the real group returned. The paths are what the voices brought back.

Nayoung’s leadership now carried two group endings and years of screen work. Chungha, Sejeong and Somi arrived with major solo catalogs. Yeonjung brought years of WJSN and musical-theatre vocal experience. Yoojung and Doyeon carried Weki Meki’s full arc. Chaeyeon, Mina and Sohye developed acting careers, while Jieqiong built substantial work in China.

The mini album’s job was therefore not to restart rookie competition. It had to produce an I.O.I sound capable of holding adult identities without turning the most commercially visible member into the sun and everybody else into reunion scenery. The best moments let recognition happen through handoffs rather than hierarchy.

The Produce 101 history needs the whole sentence

I.O.I came from the first season of Produce 101, a format that made viewers feel directly responsible for forming a group. The later vote-manipulation scandal around the franchise changed how every Produce success should be discussed, even though the first season’s final lineup occupies its own legal and evidentiary context.

The women should not be reduced either to a pure democratic fairy tale or to symbols in somebody else’s corruption story. They trained, competed, debuted under a brutally compressed contract and built one of the templates later project groups inherited. The system’s problems and the performers’ work can be true at the same time.

Their original activity ended in January 2017 because the project was designed to end. That deadline created urgency and also prevented a young group with clear public demand from developing at a normal pace. The reunion could celebrate what existed without pretending the expiry model was generous.

After LOOP: what is current now

The official anniversary channels opened in March 2026 and the Plus Chat operation ended on July 31 after the project. Existing data was preserved, while new posts and comments closed. As of August 2026, no official source has announced another I.O.I album or permanent group-management structure.

The accurate status is therefore: original project group concluded in 2017; nine-member tenth-anniversary reunion project completed in 2026; eleven-member historical identity preserved; future activity unannounced. Calling them permanently active would overpromise. Calling the reunion imaginary would be nine years out of date.

Every member profile remains one canonical person record across I.O.I, later groups, solo music and acting. A reunion does not justify cloning eleven ‘2026 versions.’ It just adds a dated chapter and exact participation relationships to the pages that already own those lives.

RaeRae verdict

I.O.I’s reunion worked because it acknowledged time instead of fighting it. Nobody needed the women to become Produce 101 contestants again. Fans needed the songs, the chemistry and the proof that an ending imposed by contract did not erase their ability to choose the name later.

The missing two members should be described with the same adult restraint. Existing schedules prevented Mina and Jieqiong from joining the project. Unless an official source says more, that is the story. Friendship tests conducted through airport photos and Instagram likes can stay in the group chat where they belong.

Bottom line: I.O.I began as eleven, returned as nine for LOOP, and ended the anniversary project with the door emotionally open but professionally unannounced. The archive will preserve all three facts without forcing them into one cleaner sentence.

Current reunion sources

• Soompi — I.O.I confirms 2026 comeback and nine-member participation
• SBS — LOOP in Seoul concert report
• AsiaWorld-Expo — official Hong Kong concert listing