Robert Keith McFerrin Jr. was born March 11, 1950, in Manhattan, into a household where singing was a profession rather than a pastime. His father, Robert McFerrin Sr., was the first African American man to sing leading roles at the Metropolitan Opera, joining the company in 1955; his mother, Sara Copper McFerrin (1924 to 2019), was a singer who later taught voice at Fullerton College. The family moved to Los Angeles in 1958, where McFerrin took piano lessons, studied clarinet and music theory, and attended Cathedral High School. He formed a group called the Bobby Mack Quartet in his high school years, which toured nationally with the Ice Follies, and went on to Cerritos College and California State University, Sacramento. For most of his twenties he worked as a pianist rather than a singer, playing lounge and dance-band gigs, and in 1978 joined the New Orleans fusion group Astral Project.

The turn came in 1977, when McFerrin decided, as he has described it in interviews, that he was meant to be a singer. He then spent roughly six years building a vocal identity from scratch, and for the first two of those years deliberately avoided listening to other singers at all so that he would not absorb anyone else's phrasing. Touring with the vocalese lyricist Jon Hendricks around 1980 gave him his first sustained exposure in the jazz world. A 1980 appearance at the Playboy Jazz Festival at the Hollywood Bowl and a 1981 set at New York's Kool Jazz Festival brought him to wider notice and led to a contract with Elektra/Musician, which released his self-titled debut in 1982 (Elektra Musician E1-60023). That first record was a conventional band date: Victor Feldman on Fender Rhodes, John Guerin on drums, Larry Klein on bass, and a studio cast around a singer still finding his frame.

He abandoned the frame almost immediately. In 1983 McFerrin went out on a solo European tour with no band, no accompaniment, and no set list, and the album drawn from those concerts, The Voice (Elektra Musician, 1984), was the first solo vocal jazz album for a major label recorded with no accompaniment and no overdubbing. It was captured across four German concerts in March 1984: Cologne on the 17th, Mannheim's Rosengarten on the 19th, Hamburg's Musikhalle on the 21st, and Stuttgart's Liederhalle on the 26th. The technique it documented, a four-octave range crossed with vocal percussion struck on his own chest, bass lines sung under melody lines, and rapid register jumps that let one throat imply a rhythm section, became the thing McFerrin was known for. Spontaneous Inventions (Blue Note, 1986) followed, with Wayne Shorter guesting on soprano saxophone on a single track, and the concert film of the same name was shot at the Aquarius Theatre in Hollywood on February 28, 1986.

The awards accumulated quickly, and nearly all of them were jazz awards. Guesting on "Another Night in Tunisia" from the Manhattan Transfer's Vocalese (Atlantic, 1985) won him a Grammy for Best Jazz Vocal Performance, Male, shared with Jon Hendricks, plus a second for Best Vocal Arrangement. His reading of Thelonious Monk's "'Round Midnight" on the soundtrack to Bertrand Tavernier's film Round Midnight (Columbia, 1986), where he sang over Herbie Hancock's piano, took another Best Jazz Vocal Performance, Male, and he won the same category again for "What Is This Thing Called Love" from Spontaneous Inventions. A fourth jazz vocal Grammy came for "Brothers," his duet with bassist Rob Wasserman on Wasserman's Duets (MCA, 1988), a track McFerrin also co-wrote and helped mix.

Then came the anomaly. "Don't Worry, Be Happy," recorded in about three hours with McFerrin supplying every sound on the track, including the bass, the percussion and the whistling, was released as the lead single from Simple Pleasures (EMI-Manhattan, 1988) and became the first a cappella recording to reach number one on the Billboard Hot 100, where it stayed two weeks. Its video featured Robin Williams and Bill Irwin. At the 1989 ceremony the song took Record of the Year, Song of the Year, and Best Pop Vocal Performance, Male, and McFerrin walked out with four Grammys that night, the fourth being the jazz vocal award for "Brothers." When George H. W. Bush's presidential campaign began using the song without authorization, McFerrin, a Dukakis supporter, declined a dinner invitation from the campaign and publicly objected; he subsequently dropped the song from his concerts, and it has never been the centre of his working repertoire. The hit is a single in a career, not the career.

What he did with the visibility was turn further inward toward improvisation. He devised circle singing in 1986, a practice in which a leader gives each section of a group a short repeating figure and improvises over the resulting layered ostinato, and in 1989 assembled Voicestra, a ten-voice improvising ensemble that carried the score for the Oscar-winning documentary Common Threads: Stories from the Quilt (1989) and dominated his album Medicine Music (EMI, 1990). Circlesongs (Sony Classical, 1997) is a full record of wordless group improvisation with no instruments at all. In parallel he took up conducting at forty, making his debut with the San Francisco Symphony in 1990 and serving as creative chair of the Saint Paul Chamber Orchestra from 1994, and he has since conducted the New York Philharmonic, the Chicago Symphony, the Cleveland Orchestra and the Vienna Philharmonic. That work has stayed conversant with the jazz side rather than separate from it: The Mozart Sessions (Sony Classical, 1996) has McFerrin conducting the Saint Paul Chamber Orchestra in two Mozart piano concertos with Chick Corea as soloist, and opens and closes each concerto with a free vocal and piano improvisation by the two of them.

The Corea partnership is the most sustained collaboration of his career. Play (Blue Note, 1992), drawn from concerts at Wolf Trap in Vienna, Virginia on June 23, 1990 and Carnegie Hall on June 27, 1990, is a duo record of standards and originals in which Corea's piano and McFerrin's voice trade lines as equals; its version of "'Round Midnight" won McFerrin his tenth Grammy for Best Jazz Vocal Performance, seven years after the same tune had won him one with Hancock. The two toured as a duo for decades afterward. McFerrin's later records kept widening the frame without leaving improvisation: Hush (Sony Masterworks, 1992) is a duo set with cellist Yo-Yo Ma recorded August 22 to 25, 1991; Bang!Zoom (Blue Note, 1995) is a band record cut with the core of the Yellowjackets; VOCAbuLarieS (Emarcy, 2010) is a large-scale multi-tracked choral work built with composer and producer Roger Treece over several years; and spirityouall (Sony Masterworks, 2013) reworks spirituals from his father's repertoire with arranger Gil Goldstein, Esperanza Spalding and Larry Grenadier splitting the bass chair. He was named an NEA Jazz Master in 2020 and given a Grammy Lifetime Achievement Award in 2023, the same year he disclosed a Parkinson's disease diagnosis and moved from Philadelphia to San Francisco. His children Taylor and Madison McFerrin are both working musicians.

McFerrin's instrument is a four-octave voice used as an entire ensemble rather than as a melody line, and the technical vocabulary is unusually wide: scat, overtone and polyphonic singing, vocal percussion struck against his own chest, sung bass figures alternating with sung melody fast enough that the ear hears two parts, and abrupt octave leaps used as rhythmic articulation rather than display. What separates him from the vocalese tradition he came out of, and from Jon Hendricks in particular, is that he largely abandoned lyrics: the material is improvised in real time and mostly wordless, closer in method to a horn player's approach to a chord sequence than to a singer's approach to a song. The a cappella solo concert, which McFerrin essentially invented as a viable jazz format with The Voice and his 1983 European tour, remains his signature setting, and his practice of conducting an audience as an improvising choir has been copied widely enough to be a genre of its own. His father's operatic training and his own conservatory-adjacent grounding in piano and clarinet show in the pitch accuracy and breath control, but the framework is jazz improvisation throughout, including in the classical work, where he routinely opens a Mozart concerto with a free improvisation. The two strands that sit outside jazz are real but narrow: "Don't Worry, Be Happy" is one enormously successful single, and the conducting career is a second occupation he took up at forty and has always run alongside, not instead of, the improvising. Seven of his ten competitive Grammys are in jazz and children's categories, and the National Endowment for the Arts named him a Jazz Master in 2020.