26-2 is a composition by John Coltrane that applies his signature harmonic substitution system to the chord changes of Charlie Parker's Confirmation, making it a contrafact of that bebop standard. Coltrane superimposes his three-tonic system of major chords connected by descending major thirds over the original progression, creating rapid key center shifts that demand exceptional harmonic fluency from improvisers. The tune was recorded on October 24, 1960, during the sessions that produced the album Coltrane's Sound, with McCoy Tyner on piano, Steve Davis on bass, and Elvin Jones on drums, though it was not released until the 1964 compilation The Heavyweight Champion. The title references the tune's relationship to Confirmation in Coltrane's personal numbering system. Like Giant Steps and Countdown, 26-2 belongs to the body of compositions Coltrane wrote to explore and demonstrate his Coltrane Changes concept, where ii-V-I progressions are connected through cycles of major thirds rather than conventional harmonic motion. Among these pieces, 26-2 stands out for the complexity of its source material, as Confirmation's changes are considerably more intricate than the simpler progressions underlying Giant Steps or Countdown. The tune remains a challenging vehicle studied by advanced jazz musicians, and the original recording from the Coltrane's Sound session features commanding solos by both Coltrane on tenor saxophone and Tyner on piano.