Josh Groban was born in Los Angeles, California, to a Jewish American father (a descendant of Polish and Russian immigrants) and a Norwegian American mother. His father converted to Christianity upon marriage, and Groban was raised an Anglican-Episcopalian. His younger brother Christopher shares a birthday with him four years later.

In 1997 and 1998, Groban attended the Interlochen Arts Camp in Michigan, majoring in musical theater, which is also when he began taking voice lessons outside of school. In late 1998, the 17-year-old Groban was introduced by his vocal coach to Grammy-winning producer/arranger David Foster. Groban worked for Foster as a rehearsal singer on a series of high-profile events, including the 1999 Grammy Awards -- where, as a stand-in for Andrea Bocelli, he rehearsed Foster's "The Prayer" with Céline Dion -- and the January 1999 inauguration of Gray Davis as governor of California.

Groban attended the Los Angeles County High School for the Arts as a theater major and graduated in 1999 and then attended Carnegie Mellon University in Pittsburgh, Pennsylvania, studying drama.

Groban left Carnegie Mellon after only one year when he was offered a recording contract at Warner Bros. Records through Foster's 143 Records imprint. With regard to signing Groban, Foster said: "I love his natural ability in the pop and rock arena, but I love his sense of classics even more. He's a true musical force to be reckoned with." Therefore, under Foster's influence, Groban's first album focused more on the classics with songs such as "Gira Con Me" and "Alla Luce Del Sole," the first ones decided on by Foster and Groban.

Soon after being picked up by Foster, Groban went on to perform "There For Me" with Sarah Brightmanon her 2000-2001 La Luna Tour. He made his recording debut by singing "For Always" with Lara Fabianon the movie soundtrack to A.I.: Artificial Intelligence (2001). Groban also became involved in many benefit shows, including the following: "The Andre AgassiGrand Slam Event For Children", singing alongside Elton John, Stevie Wonder, Don Henley and Robin Williams; "Muhammad Ali's Fight Night Foundation" which honored Michael J. Foxand others; "The Family Celebration" (2001) which was co-hosted by President Bill Clinton and his wife, Hillary Rodham Clinton, and David E. Kelley and his wife, Michelle Pfeiffer and Michael Milken's CapCure event, which raises funds for cancer research.

The singer's eponymous debut album Josh Groban was released on November 20, 2001. Over the next year, it went from gold to double-platinum. Groban's second album Closer, also produced by Foster, was released on November 11, 2003. Groban said that he believed that this second album was a better reflection of him and that his audience would be able to get a better idea of him personally from listening to it.

Two months after Closer was released, it rose on the Billboard charts from number 11 to number one. His cover of Brian Kennedy's "You Raise Me Up" became very popular on the adult contemporary charts. Groban also performed the song "Remember" (with Tanja Tzarovska) on the Troy soundtrack, "Believe" on the soundtrack to the 2004 animated film The Polar Express, and a cover of Linkin Park's "My December".

In 2004, Groban performed "Remember When It Rained," backed by a full orchestra, at the American Music Awards where he was nominated for Favorite Male Artist in the pop category. Groban and his recordings were nominated for more than a dozen awards in 2004, including the American Music Award, World Music Award, Academy Award, and a Grammy.

During the first week of September 2006, Groban's latest single entitled "You Are Loved (Don't Give Up)", was exclusively released to AOL's First Listen. It was taken from his third studio album Awake, which was officially released on November 7, 2006.