[2] Harper plays an eclectic mix of blues, folk, soul, reggae, and rock music,[3] and he is known for his guitar-playing skills, vocals, live performances, and activism.

[7] At the 40th Blues Music Awards ceremony, Harper's joint composition with Charlie Musselwhite, "No Mercy in This Land", was named Song of the Year.

[15][16] His maternal grandparents' music store, the Folk Music Center and Museum (Claremont, CA), laid a foundation of folk and blues for the artist, complemented by regular patrons Leonard Cohen, Taj Mahal, John Darnielle, and David Lindley and quotes of William Shakespeare and Robert Frost made often by his grandfather.

[20] In 1993, he toured venues in California and France with his band, Ben Harper and the Innocent Criminals, and performed with Taj Majal at Austin City Limits.

[22] He released his second album, Fight For Your Mind, in 1995, with Juan Nelson on bass, which became a college radio favorite and included several songs that Harper has played live throughout his career.

[23] The same year, the band expanded their reach to Europe and performed in the Netherlands, Switzerland, Italy, Spain, Canada, and a handful of US dates.

[24] His music received a great deal of airplay and critical acclaim in Europe and was widely played in Australia (first on Triple J radio).

[25] Jack Johnson became the opening act in late February 2001 for the last 23 cities of Ben Harper's “Innocent Criminals” tour of the United States.

Harper was featured on the album True Love by Toots and the Maytals, which won the Grammy Award in 2004 for Best Reggae Album, and showcased many notable musicians including Willie Nelson, Eric Clapton, Jeff Beck, Trey Anastasio, Gwen Stefani / No Doubt, Bonnie Raitt, Manu Chao, The Roots, Ryan Adams, Keith Richards, Toots Hibbert, Paul Douglas, Jackie Jackson, Ken Boothe, and The Skatalites.

On April 3, 2004, Harper and Jack Johnson performed with Toots and the Maytals on Saturday Night Live (season 29, episode 16), a show hosted by Donald Trump.

In the same month, Harper contributed a live recording of the song "Oppression" to For The Lady, a benefit album for jailed Nobel Peace Prize winner and Burmese pro-democracy advocate Aung San Suu Kyi.

[36] In December 2012, it was announced that Harper had co-produced lead vocalist Natalie Maines of the Dixie Chicks first solo rock album Mother.

On April 8, 2019, Harper performed as a guest artist on the seventeenth season of American Idol during the second night of the “Top 20 Duets” episode.

[citation needed] At the 40th Blues Music Awards ceremony, Harper's joint composition with Charlie Musselwhite, "No Mercy In This Land", was named as 'Song of the Year'.

Harper paid tribute to him, stating on Twitter: "Beloved husband, father, musical genius, BHIC band member of 27 years, and the finest man I've ever known.

[49] They briefly reconciled and attended the 2012 Golden Globe Awards together,[49] but Dern reactivated the divorce by filing a legal response in July 2012.

[citation needed] Harper supports Little Kids Rock, a national nonprofit organization that works to restore and revitalize music education in disadvantaged U.S. public schools.

On December 11, 2016, he played an acoustic benefit concert at Bimbos in San Francisco supporting New Light India's "Boys Home Project".

During the COVID-19 pandemic, they supported the organization's work in California, and Harper recorded a song[55] to benefit International Medical Corps’ global relief efforts.