The song was released as the second single on July 1, 2009, with promotions starting in early July. The song marked a change in the group's image, as "Fire" showcased a stronger, edgier image; in contrast, YG Entertainment CEO Yang Hyun Suk stated that "I Don't Care" would enable the group to display a softer, more feminine image.
An unplugged "reggae" version of the song was performed on SBS's Inki Gayo music show, signaling the end of promotions for the song. However, due to the remix's popularity, it was released to digital outlets on September 3, 2009.
"I Don't Care" topped various music shows, including KBS's Music Bank, M.Net's M! Countdown, and SBS's InkiGayo; it led the Music Bank chart for 5 weeks. The single was also the most downloaded song in July 2009.
By October 2012, the song has sold over 4.5 million digital copies, becoming one of the most successful singles of all-time in Korea.
The music video was premiered on June 9, 2009. The music video features the members going to a fortune teller for advice after just being blown off by their cheating boyfriends over the phone. The fortune teller stops time in order for the girls to play sabotage on their boyfriends.
^Hyun Ji-hyang (August 22, 2009). "Golden days for girl groups". Korea Herald. Retrieved December 17, 2013. their following song, "I Don't Care," is currently continuing the stream, smashing charts for five consecutive weeks. In July, it was the most downloaded song, beating out "Gee" by Girls Generation.