Jeff Parker was born on April 4, 1967, in Connecticut and grew up in Hampton, Virginia. His father, Ernie Parker, owned a clothing store called The New Breed, a name Parker later gave to his 2016 solo album. He studied at Berklee College of Music in Boston and moved to Chicago in 1991, where the city's improvised and jazz scenes became his working education. He became an associate member of the Association for the Advancement of Creative Musicians (AACM) in 1995 and recorded with the saxophonist Ernest Dawkins' New Horizons Ensemble (from 1993), the drummer Ted Sirota's Rebel Souls, and the saxophonist Pat Mallinger. He was also the guitarist in the first lineup of Brian Blade's Fellowship band, heard on its 1998 debut album, before Kurt Rosenwinkel took the chair, and he returned as one of two guest guitarists on the band's Landmarks (2014).

In the late 1990s he became a central figure in the crossover circle around the cornetist Rob Mazurek. He was a founding member of Isotope 217, whose first album, The Unstable Molecule, appeared on Thrill Jockey in 1997, and of the Chicago Underground ensembles that Mazurek and the drummer Chad Taylor built, starting with the Chicago Underground Orchestra's Playground (Delmark, 1998) and continuing with the Trio's Possible Cube (1999, on which he plays on some tracks) and Flamethrower (2000), also on Delmark. He also joined the post-rock band Tortoise, whose 1998 album TNT is regarded as its most jazz-inflected; Wikipedia dates his membership from 1996. He has stayed with the band since, recording Standards (2001), It's All Around You (2004), Beacons of Ancestorship (2009), The Catastrophist (2016), and Touch (2025), as well as the 2006 collaboration with Bonnie 'Prince' Billy, The Brave and the Bold.

His first album as a leader, Like-Coping (Delmark, 2003), was a trio date with the bassist Chris Lopes and Taylor. Through the 2000s he kept recording in many settings: Out Trios, Volume Two (2003) with the drummer Michael Zerang and the electronic musician Kevin Drumm, Song Songs Song (Delmark, 2004) with the guitarist Scott Fields, The Relatives (Thrill Jockey, 2005), albums with the bassist Joshua Abrams and with the drummer Hamid Drake's group Bindu, and the Jeff Parker Trio's Bright Light in Winter (Delmark, 2012), a second date with Lopes and Taylor. He moved to Los Angeles in 2013.

The Los Angeles years produced the work that widened his audience. The New Breed (International Anthem, June 24, 2016), his first solo project after leaving Chicago, combined his own loops, samples, and programming with the saxophonist Josh Johnson, the bassist Paul Bryan, and the drummer Jamire Williams. The solo guitar album Slight Freedom (Eremite), recorded live in real time with no overdubs, followed later in 2016, and his own site says The New York Times named both among the year's best jazz releases. Suite for Max Brown (International Anthem/Nonesuch, January 24, 2020), named for his mother, Maxine, debuted at number one on Billboard's Current Contemporary Jazz chart and was reviewed on NPR's Fresh Air. Forfolks (2021), recorded at Sholo Studio in Altadena in June 2021, is a solo guitar record that includes Thelonious Monk's "Ugly Beauty" and the standard "My Ideal," and Eastside Romp (RogueArt), a 2016 trio session with the bassist Eric Revis and the drummer Nasheet Waits, was issued in 2022. He received a United States Artists fellowship in 2022.

From 2016 until the bar closed in May 2023, Parker led a quartet with Johnson on alto saxophone, the bassist Anna Butterss, and the drummer Jay Bellerose in a weekly residency at the Enfield Tennis Academy, a small neighborhood bar in Highland Park, Los Angeles. Mondays at the Enfield Tennis Academy (Eremite, 2022) was edited from more than ten hours of two-track recordings made there between 2019 and 2021, and The Way Out of Easy (International Anthem, November 2024) captures the band's regular gig of January 2, 2023, as four continuous pieces totaling about 80 minutes. Happy Today, a live set by the same group recorded and mixed at the Lodge Room in Los Angeles, was released in May 2026. Alongside his own records he is a busy sideman and producer: he is credited on the drummer Makaya McCraven's albums In the Moment (2015), Universal Beings (2018), Deciphering the Message (2021), and In These Times (2022), and, with Butterss and Johnson, on the Red Hot Chili Peppers bassist Flea's 2026 solo debut Honora.

Parker is a guitarist, composer, and producer whose work runs across jazz, post-rock, electronic music, and hip-hop-influenced production. English Wikipedia calls him best known as an experimental musician, and his membership in Tortoise, a Chicago post-rock band, is a large part of his public profile. His jazz standing rests on more than genre labels: AACM membership since 1995, leader dates for Delmark, Eremite, Clean Feed, RogueArt, and Not Two, years inside Chicago's improvised-music community, and recent albums that critics and chart-keepers file under jazz, including a number one debut on Billboard's contemporary jazz chart. This profile therefore treats him as a jazz guitarist who also works in neighboring idioms. AllMusic's Paul Simpson describes a relaxed yet precise style that adapts to vanguard improvisation, post-bop, experimental electronics, funk, and indie rock. Since The New Breed he has built many records from sampled and looped material, borrowing ideas from beat-making and playing most of the instruments himself, while his guitar stays clean-toned and unhurried. His repertoire shows where he listens: Monk's "Ugly Beauty," John Coltrane's "After the Rain," a reworking of Joe Henderson's "Black Narcissus" retitled "Gnarciss," Marion Brown's "Similar Limits," and a cover of Frank Ocean's "Super Rich Kids." Nate Chinen of The New York Times called The New Breed a retro-futurist jazz-funk reverie. At Berklee he was close with Kurt Rosenwinkel, and his Chicago years with Dawkins and the AACM circle shaped his approach to improvisation.