"Good Day" (Korean: 좋은 날; RR: joheun nal) is a song recorded in two languages (Korean and Japanese) by South Korean singer IU. The Korean version was released on December 9, 2010, as the lead single for IU's third extended play (EP) Real. It was written by Kim Eana, while production was handled by Lee Min-soo. The Japanese version was originally included on IU's first Japanese extended play I□U, released on December 14, 2011, before being released on March 21, 2012, as IU's first single album Good Day.
"Good Day" received generally positive reviews by music critics. Billboard magazine crowned it as the best K-pop song released in the 2010s. Commercially, the song debuted atop the Gaon Digital Chart, topping the chart for five weeks and becoming the sixth best-selling single in South Korea, selling more than 4.4 million digital units. The Japanese version reached the top five on the Oricon Singles Chart, and sold more than 30,000 physical copies in the country.
"Good Day" was released on December 9, 2010, simultaneously with the singer's third extended play (EP) Real. On November 15, 2011, Loen announced, that IU was signed to EMI Music Japan and was set to release an extended play with her greatest hits recorded in Japanese, on December 14, 2011, titled I□U.[1]
The Korean version of "Good Day" was written by Kim Eana, while production was handled by Lee Min-soo. In terms of musical notation, the song is composed in the key of A♭ Major, with a tempo of 128 beats per minute, and runs for 3:53.[2]
Writing for New Straits Times, Bibi Nurshuhada Ramli described "Good Day" as IU's breakout song.[3]South China Morning Post's Sylvia Issa described the songs as a "unique musical phenomenon".[4] In November 2019, Billboard magazine compiled a list of the 100 Greatest K-Pop Songs of the 2010s, with the single "Good Day" ranking at number one.[5]
Commercially, "Good Day" debuted at number one of the South Korean singles chart on the 51st issued week of 2010.[6] It topped the chart for five consecutive weeks, falling to no. four on the fourth issued week in 2011. The song held the record for the most weeks at number one until 2018, when it was beaten by iKon "Love Scenario". Furthermore, the single topped the monthly singles chart in December 2010.[7] It was selected as Gallup Korea's Song of the Year in 2011.[8]
^韓国の“国民の妹”IU、来春日本デビュー決定 [Korea's "Nation's little sister" IU to debut in Japan spring next year]. Oricon News (in Japanese). Archived from the original on June 25, 2018. Retrieved August 12, 2020.
^"IU – Good Day". Musicstax. Archived from the original on October 18, 2020. Retrieved August 12, 2020.
^Nurshuhada Ramli, Bibi (December 29, 2019). "#Showbiz: Big love for IU on every note". New Straits Times. New Straits Times Press. Archived from the original on December 30, 2019. Retrieved January 26, 2020.
^ ab2010년 51주차 Digital Chart [Week 51 of 2010 Digital Chart]. Gaon Music Chart (in Korean). Korea Music Content Association. Archived from the original on March 7, 2015. Retrieved July 2, 2019.
^2010년 12월 Digital Chart [December 2010 Digital Chart]. Gaon Music Chart (in Korean). Korea Music Content Association. Archived from the original on November 26, 2020. Retrieved January 26, 2020.
^"'레전드' 싸이 '강남스타일' 21세기 최고 히트곡 등극[창간 20주년 설문]" ['Legend' Psy's 'Gangnam Style' Becomes 21st Century's Greatest Hit Song [20th Anniversary Survey]]. Star News (in Korean). Naver. September 6, 2024. Retrieved September 16, 2024.
^"K-POP 명곡 100" [Top 100 K-pop Masterpieces]. Melon (in Korean). August 27, 2021. Retrieved July 25, 2023.
^"대중음악계 10년史..최고 히트곡 톱10·연도별 190選" [10 years of popular music .. Top 10 hits, 190 songs by year]. Star News (in Korean). September 15, 2014. Retrieved October 2, 2021.
^아이유, 한국대중음악상 3관왕…시상식 불참 ‘아쉬워’ [IU, Korea pop the Triple Crown ... Attendance at the awards ceremony]. Segye (in Korean). February 29, 2012. Archived from the original on January 12, 2021. Retrieved January 26, 2020 – via Naver.
^週間 シングルランキング: 2012年04月02日付 [Weekly Singles Ranking] (in Japanese). Oricon. April 2, 2012. Archived from the original on January 26, 2020. Retrieved January 26, 2020.
^2011년 Digital Chart [2011 Digital Chart]. Gaon Music Chart (in Korean). Korea Music Content Association. Archived from the original on September 24, 2015. Retrieved January 26, 2020.
Gaon Download Chart 2010년 [Gaon Download Chart 2010]. Gaon Music Chart (in Korean). Korea Music Content Association. Archived from the original on October 18, 2013. Retrieved March 28, 2015.
2011년 Download Chart [2011 Download Chart]. Gaon Music Chart (in Korean). Korea Music Content Association. Archived from the original on April 2, 2015. Retrieved March 28, 2015.
2012년 Download Chart [2012 Download Chart]. Gaon Music Chart (in Korean). Korea Music Content Association. p. 4. Archived from the original on August 15, 2016. Retrieved December 19, 2016.
Gaon Download Chart 2013년 12월 1주차 [Gaon Download Chart Week 1 of December in 2013]. Gaon Music Chart (in Korean). Korea Music Content Association. Archived from the original on December 20, 2013. Retrieved April 17, 2015.
Gaon Download Chart 2013년 12월 2주차 [Gaon Download Chart Week 2 of December in 2013]. Gaon Music Chart (in Korean). Korea Music Content Association. Archived from the original on February 22, 2014. Retrieved April 17, 2015.
2014년 Download Chart [2014 Download Chart]. Gaon Music Chart (in Korean). Korea Music Content Association. p. 4. Archived from the original on August 15, 2016. Retrieved December 19, 2016.
2015년 Download Chart [2015 Download Chart]. Gaon Music Chart (in Korean). Korea Music Content Association. p. 3. Archived from the original on August 15, 2016. Retrieved December 19, 2016.
^オリコンランキング情報サービス「you大樹」 [Oricon Ranking Information Service 'You Big Tree']. Oricon (in Japanese). Archived from the original on December 2, 2018. Retrieved January 15, 2014.
^정재형, 아이유 '좋은 날' MV 카메오 출연 '화제' [Jung Jae-hyung makes a cameo in IU's 'Good Day' MV as an agent]. Asiae (in Korean). Asian Economy. December 8, 2010. Archived from the original on July 13, 2019. Retrieved July 13, 2019.
^Japan debut single 『Good Day』(初回生産限定盤)(Type A)(DVD付) [Japan debut single [Good Day] (First Press Limited Edition Type A) (with DVD)] (in Japanese). EMI Records Japan. March 21, 2012. Archived from the original on May 11, 2021. Retrieved July 13, 2019 – via Amazon.