John Clayton Mayer (/ˈmeɪ.ər/; born October 16, 1977) is an American singer-songwriter and producer. He was born in Bridgeport, Connecticut, and raised in nearby Fairfield. He attended Berklee College of Music in Boston, Massachusetts, but disenrolled and moved to Atlanta, Georgia in 1997 with Clay Cook. Together, they formed a short-lived, two-man band called Lo-Fi Masters. After their split, Mayer continued to play local clubs—refining his skills and gaining a following. After his appearance at the 2001 South by Southwest Festival, he was signed to Aware Records, and then Columbia Records, which released his first EP, Inside Wants Out. His following two full-length albums—Room for Squares (2001) and Heavier Things (2003)—did well commercially, achieving multi-platinum status. In 2003, he won the Grammy Award for Best Male Pop Vocal Performance for the single "Your Body Is a Wonderland".

Though Mayer started his career mainly performing acoustic rock, he began moving towards the blues genre that had originally influenced him as a musician. By 2005, he was collaborating with blues artists such as B. B. King, Buddy Guy, and Eric Clapton. Forming the John Mayer Trio, he released a live album in 2005 called Try!, and his third studio album Continuum in 2006. Both albums received wide critical acclaim, and Continuum earned Mayer a 2007 Grammy Award for Best Pop Vocal Album. He also won Best Male Pop Vocal Performance for "Waiting on the World to Change". That album was followed by Battle Studies in 2009, a return to pop, with a number-one grossing tour.

After having several controversial incidents with the media, Mayer withdrew from public life in 2010 and began work on a follow-up album, called Born and Raised, that would draw inspiration from the 1970s pop music of Laurel Canyon. However, the discovery of a granuloma on his vocal cords delayed the release of the album until May 2012, and ultimately forced him to cancel the planned tour. Even so, the album enjoyed a generally favorable reception, though it failed to produce any hit singles. After extensive treatments for his vocal problems—and a two-year hiatus—Mayer began performing as a singer again in January 2013, and that year released the album, Paradise Valley. The album is named for where he lives in Montana and features country music influences. By 2014, he had sold a total of over 20 million albums worldwide.

Mayer's secondary career pursuits extend to television hosting, comedy, and writing; he has penned columns for magazines such as Esquire. He supports various causes and has performed at charity benefits. He is a watch aficionado (with a collection valued into the tens of millions of dollars), and has been on the jury at the Grand Prix d’Horlogerie de Genève. His affinity for dating A-list stars (and history of giving revealing interviews about them), has contributed to his reputation in the media as a lothario. He currently lives in Montana.