Mayer was born on October 16, 1977, in Bridgeport, Connecticut, to Richard (a high-school principal) and Margaret Mayer (a middle-school English teacher). He grew up in nearby Fairfield, the middle child between older brother Carl and younger brother Ben. His father is Jewish, and Mayer has said that he relates to Judaism. As a middle school student, Mayer became close friends with future tennis star James Blake, and they often played Nintendo together after school.
Philanthropy
In 2002, Mayer created the "Back to You" Fund, a nonprofit organization that focuses on fundraising in the areas of health care, education, the arts and talent development. The foundation auctions exclusive John Mayer items, such as guitar picks, T-shirts and signed CDs. The auctions have been successful, with some tickets selling for more than seventeen times their face value.  Mayer participated at the East Rutherford, New Jersey location of the Live Earth project, a musical rally to support awareness for climate change held July 7, 2007.  Mayer performed at a number of benefits and telethons for charity throughout his career. He has participated in benefits for the Elton John AIDS Foundation. In response to the Virginia Tech massacre, Mayer (along with Dave Matthews Band, Phil Vassar, and Nas) performed a free concert at Virginia Tech's Lane Stadium on September 6, 2007. followed by an appearance with Rob Thomas at the Annual Holiday Concert at Blythedale Children's Hospital in Valhalla that winter. On December 8, 2007, Mayer hosted the first annual Charity Revue, a tradition he has continued each year. Charities who have benefited from the concerts include Toys for Tots, Inner City Arts and the Los Angeles Mission. CDs and DVDs of the first concert were released under the title Where the Light Is in July 2008. Mayer appeared on Songs for Tibet: The Art of Peace, a celebrity initiative to support Tibet and the 14th Dalai Lama, Tenzin Gyatso. Mayer (along with Keith Urban) headline Tiger Jam 2011 in Las Vegas to help raise around $750,000 for the Tiger Woods Foundation. In January 2013, Mayer participated with Zac Brown in a benefit concert in Bozeman, Montana where they raised more than $100,000 for firefighters who battled a wildfire in the summer of 2012 in Paradise Valley that destroyed 12,000 acres.

Q: what is a charity he works for?
A: Mayer created the "Back to You" Fund,

Q: what does this charity do?
A: focuses on fundraising in the areas of health care, education, the arts and talent development.

Q: how does the charity raise money?
A: The foundation auctions exclusive John Mayer items,

Q: did the charity earn a lot of money?
A: The auctions have been successful, with some tickets selling for more than seventeen times their face value.
what is a type of philanthropy he works with?
Mayer participated with Zac Brown in a benefit concert in Bozeman, Montana where they raised more than $100,000 for firefighters
Mayer participated with Zac Brown in a benefit concert in Bozeman, Montana where they raised more than $100,000 for firefighters