Chords in F Lydian

F Lydian is built from the notes F, G, A, B, C, D and E. It uses no sharps or flats at all. Harmonising that scale in thirds gives seven chords — 3 majors, 3 minors and 1 diminished — starting on F as the I. The chord on the fifth degree is C, a major V, so F Lydian has the leading tone that makes a C-to-F cadence sound final.

Beyond those seven, F Lydian commonly borrows Fm (i), Gdim (iiø), Ab (bIII), Bbm (iv) and Cm (v) from the parallel minor — the mixture chords that give a progression somewhere unexpected to go.