Nitzan Bar was born in Jerusalem in 1998 and grew up in Modi'in, where the family moved when he was six. Music was already in the house: his father, Atche Bar, is a veteran Israeli musician who worked in his own youth with Gali Atari and Miki Gavrielov, and kept a studio at home. His older brother Tomer Bar is a pianist and composer who has played in the same rooms and on the same records. Bar started on drums at three, moved to guitar at nine, began studying the instrument formally at eleven, and found jazz at twelve. His first music teaching came in the third grade at the Democratic School in Modi'in, under Shahar Galina.

The recognition arrived early. In July 2014, at sixteen, he was one of ten guitarists accepted worldwide into the Montreux Jazz Festival's guitar competition in Switzerland, and from that year he held a grant from the America-Israel Cultural Foundation. In the winter of 2016 he played the Red Sea Jazz Festival with the pianist Ruslan Sirota alongside Gilad Abro and Amir Bresler. That December, at the second Jerusalem Jazz Festival at the Israel Museum, running under the artistic direction of the trumpeter Avishai Cohen, his own trio made its festival debut, with Abro on bass and Bresler on drums and the seventeen-year-old guitarist Omri Keren as guest. The programme paired Bar's original pieces with music by Pat Metheny and John Scofield. He was eighteen, and he enlisted in the Israel Defense Forces as an outstanding musician two days after the festival closed.

Three working associations shaped the years that followed. He joined Daniel Zamir's band, playing both in the full group and in a saxophone-and-guitar duo with Zamir, including two Romanian festival dates. He joined the flautist Mattan Klein's group. And after finishing his studies he took a guitar chair in the Israel Jazz Orchestra, the twelve-piece big band founded in 2003 by the trombonist Avi Leibovich and known in Israel simply as the Orkestra. That last appointment is the one that explains the shape of his résumé. The orchestra's standing practice is to build programmes around guest artists from outside jazz, and its collaborators list runs to Yoni Rechter, Ester Rada, Chava Alberstein, Shlomo Gronich, Shem Tov Levi and Shlomi Shaban. Bar has worked with most of them, and the pop names on his credit list came to him through a jazz orchestra rather than around one. Hebrew Wikipedia's article on the orchestra files him among its former and guest guitarists next to Yonatan Albalak, and its former keyboard chairs include both Nitai Hershkovits and his brother Tomer Bar.

He recorded his own first album in the summer of 2017 and released it on August 5, 2018 as The Scratch, nine original pieces running just under an hour. In March 2020 the Zamir duo was booked into the Opus Jazz Club at the Budapest Music Center as part of the Israeli Jazz Spring series, a date carried on the Europe Jazz Network's calendar, and the club's own copy described a duo album due within months of the tour. Israel's quarantine measures cancelled the concert on March 10, the day before it was to happen, and no duo record has appeared since. That August, back in Israel, he recorded at Bardo Studios with the saxophonist Asaf Harris; the results came out on Ubuntu Music on May 6, 2022 as Walk of the Ducks, with Bar on guitar in a quintet completed by Guy Moskovich on piano, Omri Hadani on bass and David Sirkis on drums.

His work as a leader took an unexpected turn in the same period. On October 22, 2021 he issued two albums at once, NITZ A and NITZ B, a pair of Hebrew-language song records on which he writes the words and music, sings, and plays guitars, bass, drums, mandolin and bouzouki himself. A string quartet including the cellist Maya Belsitzman appears on four tracks of NITZ A, Tomer Bar plays keyboards on both, and Avri Borochov shares the mixing credit on the first. A third Hebrew album, Levad Beyachad, followed on April 14, 2024. The jazz playing did not stop while this was going on: he shared a two-guitar billing with Yoav Eshed at TASSA in Tel Aviv on August 11, 2023, and turned up on the Imma Express single "Radio Kinshasa" alongside Eshed in 2024.

The last two years have put him on two of the more visible Israeli jazz records of the decade. He holds the guitar chair through the whole of Ofri Nehemya's debut Time Traveler, cut at Kitcha Studio in Tel Aviv on January 28 and 29, 2023 and released by Adhyaropa Records on May 2, 2025, in a quartet with Nehemya on drums, Tomer Bar on piano and Tal Mashiach on bass. And on March 6, 2026 he appears on Shai Maestro's The Guesthouse for Naive, playing guitar on "Moon of Knives," one of eleven pieces on a record whose cast also includes Immanuel Wilkins, Gadi Lehavi and Nehemya. In November 2025 he and Zamir recorded together again, on two singles issued by the group Enlightened Octopus.

Bar plays a clean, forward-set electric guitar built on the post-bop and fusion line that runs from Pat Metheny and John Scofield, both of whom were in his trio's book at eighteen, and he has been described in the Israeli press since his teens as a virtuoso. What distinguishes him from the many Israeli guitarists working out of that same lineage is rhythm rather than harmony. The Budapest Music Center's copy for the Zamir duo, the fullest published description of his playing, singles out a shared and unusually exact sense of time: two players floating on the beat or over it, breaking the bar line and landing together on the one, working from precision and listening rather than density, and folding Hasidic melody, Arabic modal thinking and Indian rhythmic cycles into a hard-core jazz frame. The account of Time Traveler that this catalogue's profile of Ofri Nehemya gives reaches for the same two reference points, Metheny and Scofield, for the prominence Nehemya gives Bar's guitar. Alongside all of it he has built a separate body of Hebrew-language songwriting under his own name, singing and playing nearly every instrument himself, which puts him in a small group of Israeli jazz players who lead a second career as songwriters without letting either one absorb the other.