"If I Ain't Got You" is a song recorded, written, and produced by American R&B-soul singer Alicia Keys for her second studio album, The Diary of Alicia Keys (2003). Released in February 2004 as the album's second single, the song peaked at number four on the Billboard Hot 100 and became Keys' second consecutive R&B chart-topper, remaining atop the Hot R&B/Hip-Hop Songs for six weeks. It reached number three on the Billboard Hot 100 Year-End chart for 2004. The song is Keys' longest chart-running single on the Hot 100, with a chart run of forty weeks; it was also the first song by a female artist to spend over a year on the Hot R&B/Hip-Hop Songs, with fifty-six weeks. The song received two nominations at the 2005 Grammy Awards, for Song of the Year and Best Female R&B Vocal Performance, winning in the later one.
A remix featuring Usher, a Kanye West Radio Mix and a Spanish-language version featuring Arturo Sandoval appear on the bonus CD of select international pressings of The Diary of Alicia Keys. The song is featured in the 2004 PlayStation 2 karaoke game Karaoke Revolution Volume 3.
The single's music video, directed by Diane Martel, is set in a wintry New York City and features a cameo by rapper-actor Method Man as Keys' boyfriend.
The single cover depicts Keys similarly to the subject of Man Ray's 1924 painting Le Violon d'Ingres.