[3] Born and raised in Fukuoka prefecture, she played live at various locations in her hometown before being noticed by Sony Music Japan when she was 17 years old, and released her debut single months later.
Her singles, however, were only met with moderate success until the breakout "Good-bye Days", which charted for 44 weeks on Oricon and marked her as one of the Japanese music industry's rising stars.
[8] Self-described as shy and horrible at talking to others as a child, she would play outside by herself in mountains, rivers, by the sea and in rice paddies.
[9] During her third year in primary school, she was influenced by her mother to begin writing a journal of her feelings and tried to compose them into poems.
Yui's professional career began in March 2004 when, at the recommendation of her cram school instructors, she applied for an audition hosted by Sony Music Japan.
Although "I Know" was incomplete at the time, the judges were able to get a glimpse of what would later be dubbed "Yui-go" (YUI語), or Yui-speak, nonsensical English hummed to a tune during her songwriting process.
On December 24, 2004, Yui released her debut single, "It's Happy Line", under the indie label Leaflet Records, coupled with the track "I Know," although the pressing was limited to only 2,000 copies in her home area.
[14] The music in Fukigen na Gene was eventually based on her songs "Feel My Soul" and "It's Happy Line."
[15] Yui made her acting debut in the full-length feature film Song of the Sun (Taiyou no uta, タイヨウのうた),[16] which opened on June 17, 2006.
Due to the success of Can't Buy My Love, Yui's previous album, From Me to You charted once again, adding another 9,000 copies to the Oricon counting.
The title track is the theme song to the film Closed Note (クローズド・ノート) (starring Erika Sawajiri, also of Stardust).
During this time, her previous two albums were re-released as Winter Sleeve Editions in alternative covers taken from her "Love & Truth" photoshoot.
[24] Yui composed the song as a "mysterious and sad sounding" insert for the television drama 4 Shimai Tantei Dan.
While writing the song, she attempted to convey a feeling of saying "I'm fine" in order to not worry one's lover, and how during such occasions, we realize little things we don't normally notice.
The 10th track on the album, titled "Oh Yeah", was used as the opening theme to Mezamashi TV, a morning television show.
The limited edition version of the album included a DVD which contained music videos of her previous singles and live footage of her Nippon Budokan show.
Yui released her B-side compilation album, My Short Stories,[29] on November 12, 2008, which debuted at number 1 on Oricon.
"[30] Yui is the second female artist whose B-side compilation album topped the charts, after Seiko Matsuda's Touch Me in 1984.
The track was chosen as the first opening theme of the new season of the Fullmetal Alchemist: Brotherhood anime, premiering on April 5, 2009.
[36] On July 14, 2010, Yui released her fourth studio album Holidays in the Sun, which included her five singles from "Summer Song" to "To Mother".
It became her fourth straight album to top the Oricon charts, eventually selling over 300,000 copies and attaining the certification of Platinum.
On June 16, 2011, Yui traveled to Hong Kong for her first overseas concert at the AsiaWorld-Expo Arena, performing to a capacity audience of 14,000 people.
[41] Yui visited schools in stricken areas from the 2011 Tōhoku earthquake and tsunami on July 7, 2011, and performed a charity concert.
[44][45] She started her fifth major tour on November 11, 2011, to promote her recent album with cruising as its principal thematic element.
[49] In a video uploaded to Yui's official Vevo channel on December 18, 2012, she announced that she would be taking a break from music.
[51] The band has since released four digital and Japan-only singles; "Tsuki (月)," "Kamisama (神様)," "Natsu/Aki (夏/秋)" and "Subarashii Sekai (素晴らしい世界)".
On March 27, 2014, Yui revealed in her band blog that she had been diagnosed with a panic disorder, which resulted in the cancellation of some presentations.