John Carl "Jon" Hendricks was born September 16, 1921, in Newark, Ohio, one of fourteen siblings in the family of an African Methodist Episcopal pastor. The family moved several times before settling in Toledo, where the Hendricks household regularly hosted touring jazz musicians and Jon began singing professionally at parties and dinners around age seven. A neighbor on the same Toledo street, a young piano prodigy named Art Tatum, gave him informal early musical guidance. As a teenager Hendricks sang with a radio harmony group called the Swing Buddies, contributing money to support the family, and worked around Toledo and Detroit until he was drafted.

Hendricks served in the U.S. Army during World War II, taking part in the Normandy landings in June 1944 before being attached to quartermaster headquarters in France. After Black soldiers in his unit were targeted by military police for socializing with French women, Hendricks and others went on the run with army supplies before being recaptured; a court-martial in November 1945 sentenced him to eleven months in the stockade. He returned home to study pre-law at the University of Toledo on the G.I. Bill, teaching himself drums along the way, before deciding to pursue music and lyric-writing full time. He moved to New York in 1952, where he began writing songs and absorbed the emerging vocalese style pioneered by King Pleasure and Eddie Jefferson, who set lyrics to recorded jazz instrumental solos.

In New York, Hendricks partnered with singer Dave Lambert on vocalese arrangements of Count Basie big-band recordings; unable to assemble enough singers to cover all the horn parts live, the pair (soon joined by singer Annie Ross) turned to overdubbing their own voices multiple times in the studio. The result, Sing a Song of Basie (1958, ABC-Paramount, with pianist Nat Pierce, bassist Eddie Jones and drummer Sonny Payne backing the trio, produced by Creed Taylor), became a surprise bestseller and a landmark in recorded jazz: Ross sang the high trumpet parts, Hendricks the fast tenor-saxophone lines, both carrying Hendricks's own lyrics note for note against the original solos. Lambert, Hendricks & Ross became "The Hottest New Group in Jazz" on the cover of DownBeat in September 1959, and their 1961 album High Flying (Columbia, with the Ike Isaacs Trio, produced by Teo Macero) won the Grammy Award for Best Performance by a Vocal Group at the 1962 ceremony. Hendricks's lyric-writing over this period included setting words to Ben Webster's tenor solo on Duke Ellington's "Cotton Tail" and composing "I Remember Clifford" (a tribute to trumpeter Clifford Brown, set to Benny Golson's tune), later recorded by numerous singers. When Annie Ross left the group in 1962 due to illness, singer Yolande Bavan replaced her as Lambert, Hendricks & Bavan; the group disbanded for good in 1964, and Dave Lambert was killed in a highway accident in 1966.

Hendricks pursued a solo and small-group career through the 1960s and 1970s, recording A Good Git-Together (1959, World Pacific, with guitarist Wes Montgomery and saxophonist Pony Poindexter) and staging Evolution of the Blues Song, a narrated musical history of the blues, at the Monterey Jazz Festival in 1960. He recorded and toured with George Russell, sang on Art Blakey and the Jazz Messengers' Buhaina (1973), and moved his family first to Mill Valley, California, and then, in 1968, to London for five years, partly to give his children a different environment. Back in the Bay Area in the 1970s, he worked as a jazz critic for the San Francisco Chronicle, released Tell Me the Truth (1975, Arista, produced by Ben Sidran, with guitarist Boz Scaggs and Hendricks's wife Judith among the credited musicians), and began a long teaching career at Sonoma State University and the University of California, Berkeley.

Hendricks's later decades brought renewed visibility. His 1982 album Love (Muse, billed to Jon Hendricks & Company) featured his daughter Michele Hendricks; in 1985 he wrote all the lyrics for the Manhattan Transfer's Vocalese, an album built from his vocalese technique that drew a then-record-tying twelve Grammy nominations and won two, including Best Jazz Vocal Performance, Duo or Group. Hendricks himself won the Grammy for Best Male Jazz Vocal Performance that year for his own vocal turn with Bobby McFerrin on "Another Night in Tunisia," a track from that same album. His 1990 album Freddie Freeloader (Denon, produced by Hendricks) assembled an all-star cast including George Benson, Al Jarreau, Bobby McFerrin, Wynton Marsalis, Stanley Turrentine, and the Count Basie Orchestra, built around a Miles Davis composition. He was named an NEA Jazz Master in 1993, sang in Wynton Marsalis's Pulitzer Prize-winning oratorio Blood on the Fields, and in 2000 returned to the University of Toledo as Distinguished Professor of Jazz Studies, receiving an honorary doctorate and later becoming the first American jazz artist to lecture at the Sorbonne in Paris. He continued performing into his nineties, touring in 2003 with the "Four Brothers" vocal quartet alongside Kurt Elling, Mark Murphy, and Kevin Mahogany, guesting on the 3 Cohens' Family (2011) alongside Anat Cohen, Yuval Cohen, and Avishai Cohen, and appearing on record as recently as 2016. Jon Hendricks passed away on November 22, 2017, in Manhattan, at age ninety-six; his full lyricization of Miles Davis's Miles Ahead had its concert premiere in New York earlier that same year.

Hendricks did not invent vocalese outright (King Pleasure and Eddie Jefferson preceded him in setting words to recorded jazz solos), but he is the figure most responsible for turning it into a fully developed art form and a working career, writing dense, witty, syllable-perfect lyrics that tracked entire instrumental solos, choruses, and even whole horn sections at the speed the originals were played. Critic Leonard Feather called him the "Poet Laureate of Jazz," and Time magazine dubbed him the "James Joyce of Jive" for the sheer verbal density of his writing. His work with Lambert, Hendricks & Ross established the vocalese trio as a viable jazz format and directly shaped the vocabulary of later vocalese and vocal-jazz singers, including the group he mentored into being with the Manhattan Transfer's Vocalese, and singers such as Kurt Elling, Mark Murphy, and the New York Voices who extended the same tradition.