Girl's Day (Korean: 걸스데이) is a South Korean girl group formed by Dream T Entertainment in 2010. The group consists of members Sojin, Minah, Yura, and Hyeri. Members Jisun and Jiin officially left the group in 2010, while Jihae left in late 2012.
In order of release, the group's biggest hits include "Twinkle Twinkle", "Hug Me Once", "Expect", "Something", "Darling", and "Ring My Bell", all of which have sold more than one million digital copies each.
Over the span of their career, Girl's Day has endorsed over 20 brands, including LG Electronics, Ezaki Glico's Pocky, Lotte World, Nexon and Bullsone. Girl's Day ranked 13th in Korea Power Celebrity in 2015, a list ranking Korea's most powerful and influential celebrities. In 2016, the group ranked 26th, whereas member Hyeri ranked 3rd.In 2019, the four members decided not to renew their contracts with Dream T Entertainment, but have stated that they haven't disbanded. Their last release was the EP Everyday #5 in 2017.