Exo (Korean: 엑소; RR: Ekso; stylized in all caps) is a South Korean-Chinese boy band based in Seoul formed by SM Entertainment in 2011 and debuted in 2012.

The group debuted with twelve members separated into Exo-K (Suho, Baekhyun, Chanyeol, D.O., Kai and Sehun) and Exo-M (Xiumin, Lay, Chen, Kris, Luhan and Tao).

The group's later works expanded on their early commercial success, with their subsequent Korean studio albums combined with their repackages each selling over one million copies.

Outside of music, the group members have endorsed brands such as Nature Republic and Samsung and participate in philanthropic efforts such as Smile For U, an ongoing project by SM Entertainment and UNICEF that began in 2015.

In 2011, SM Entertainment founder Lee Soo-man revealed plans to debut a new boy band that would be divided into two sub-groups, promoting the same music simultaneously in South Korea and China by performing songs in both Korean and Mandarin.

[8][9] In 2008, Chanyeol, who had been studying at an acting academy, and Sehun, who was first scouted by SM Entertainment at the age of thirteen and then went through four auditions in two years, were the next members to become trainees.

All versions of XOXO collectively sold over one million copies, making Exo the first South Korean artists to reach that milestone in 12 years.

[38] On October 10, Luhan also filed a lawsuit against SM Entertainment to terminate his contract,[39][40] citing health problems and different treatment than the group's Korean members.

[46] Tao was absent during promotions for Exodus due to injuries and, on August 24, became the third member to file a lawsuit against SM Entertainment to terminate his contract.

On the day of release, the album sold 147,000 copies and reached the top of the Oricon chart, becoming the all-time best-selling debut single in Japan by a Korean artist.

[64] Selling over 158,000 copies, it reached number two on the Oricon weekly chart and became the band's second Japanese single to receive a platinum certification from the Recording Industry Association of Japan.

[84] The Russian two time Olympic silver medalist and figure skating world champion Evgenia Medvedeva also drew media attention for her support of Exo.

[97] The group debuted several songs from the album live through Exo Planet 5 – Exploration encore concerts in December 2019, which also served as the tour's concluding shows.

[98] In February 2020, SM Entertainment revealed that Exo would prioritize solo and sub-unit activities in 2020 due to multiple members being on hiatus to fulfill their mandatory military service.

[115] In response to SM, it was confirmed that Chen, Baekhyun, and Xiumin were exploring ways to continue promoting as Exo members following the results of the lawsuit.

[60] Tao went on an official hiatus during Exodus promotions due to injury and filed a lawsuit against SM on August 15, 2015, formally leaving Exo on March 15, 2018.

[155][156][157] Billboard applauded the band's single "Universe" from the 2017 EP of the same name, stating, "With soaring, emotive vocals courtesy of the Exo members, 'Universe' is a power ballad that showcases the group's strengths.

"[158] Most of Exo's songs blend pop, hip-hop, and R&B with electronic dance music genres such as house and trap and are produced with onstage performance in mind.

[159][160] The group has frequently worked with veteran Korean and international producers, including Kenzie, Dean, LDN Noise, The Underdogs, and MARZ Music.

"[163][164] The group explored a more "mature" and "dark" sound in 2016 with the release of their third studio album, Ex'Act, which was marked by an increased use of synth-pop and electronic dance music styles such as house.

"[180] Yahoo wrote that "during one segment, the boys stood on an elevated hexagon-shaped stage (modeled after the band's logo), and danced sensually while water rained down on them from above.

"[181] On their stage design, Music Mind noted Exo's use of "not only ... the stage-lights and the lightsticks, but also [a] multitude of special effects like water, flames, and fireworks, not to mention huge screens positioned both on the substage and across the whole perimeter of the venue".

"[183] Covering a 2018 concert in Singapore, Bandwagon remarked that after their "fourth headlining tour [in] four years ... you might [assume] their setlist and stages would be repetitive and stale.

[179] In 2016, AsiaOne said "Exo are turning into an omnipresent, unstoppable global force," citing their worldwide popularity, critical acclaim, and large fandom size.

[199] Exo's work has influenced numerous artists, including MVP,[200] Kim Dong-han,[201] NCT 127,[202] Wanna One,[203] Ong Seong-wu and Kang Daniel.

[210] On November 3, 2017, Exo received a Prime Minister Commendation at the Korean Popular Culture and Arts Awards, an honor bestowed in recognition of public service and/or excellence in a given field.

"[211] Exo has maintained numerous endorsement deals throughout the group's career, and has been named multiple times as having the most powerful brand reputation among K-pop artists by the Korean Business Research Institute.

[224][225] Also in 2016, the group became the official faces of international clothing brand SPAO's spring collection, which included limited-edition postcards and posters for customers.

[228] Following this announcement, Chanyeol, Kai, and Sehun attended the grand opening of the MLB store in Times Square, Hong Kong, on March 23.

[235][236][237][238] In 2015, Exo began participating in Smile For U, a joint SM Entertainment and UNICEF project that supports music education for children in Asia.