"Iris" is a song by American alternative rock band Goo Goo Dolls. Originally written for the soundtrack of 1998 film City of Angels, the song was later included on the band's sixth album Dizzy Up the Girl. "Iris" has contributed greatly to the band's success. The song's time signature alternates between 4
4 and 3
4, and features an unusual guitar tuning in which most of the strings are tuned to D, lending the guitar a chorus-like effect.

Besides becoming one of the biggest alternative rock staples of the 1990s, "Iris" also remains one of the biggest crossover hits in the history of popular music, crossing over from modern rock radio to pop and adult contemporary radio, reaching number one on all of these formats and becoming the most played song of 1998 for all formats.

Upon its release, "Iris" became second of a string of hits from the film's soundtrack, City of Angels: Music from the Motion Picture. (The first was Alanis Morissette's "Uninvited" and the third was Sarah McLachlan's "Angel"). The song debuted at #66 on the Billboard Hot 100 Airplay chart on April 18, 1998, and eventually spent a record of 18 weeks at number one in Hot 100 Airplay. However it was not allowed to chart on the Billboard Hot 100 because no commercial single had been released. In December 1998, just after the song airplay has peaked, the rules changed to allow airplay-only songs onto the chart. As a result, the song debuted and peaked at number 9 and stayed on the chart for 14 weeks. On the Mainstream Rock Tracks chart, "Iris" peaked at number eight. The song was the band's 2nd number one hit on the Modern Rock Tracks chart since their 1995 hit "Name" and Iris stayed at number one for five weeks and the song also hit number one on the Mainstream Top 40 chart for four weeks. The song spent a then-record 17 weeks at number one on the Billboard Adult Top 40 chart (beating No Doubt's 15-week run at number one with "Don't Speak" in 1996–97). The Goo Goo Dolls performed the song on October 20, 2001 at Madison Square Garden as part of The Concert for New York City to raise money for victims of the September 11 attacks.

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