Fantaisie-Impromptu Op. 66: opening chords and form

C♯ minor138 bars4/4Allegro agitatoLevel 7 of 89-page PDF

The team at Chopin Left HandUpdated September 2026

Form

Intro1–4

A5–12

B13–24

A′25–34

T35–40

C41–82

A83–90

B91–102

A′103–112

T113–118

Coda119–138

Intro G♯, then C♯ minorA themeB the bass climbsA′ theme again, extendedT chromatic run, then octavesC D♭ major, slowerA theme againB the bass climbs againA′ theme extended againT run and octaves againCoda C♯ major

Bars 5–9 in C♯ minor

bar 5C♯mi

bar 6C♯mi

bar 7D♯m7♭5iiø⁷

bar 8G♯7V⁷

bar 9C♯mi

Sections

Intro and A (1–12): the theme

After a G♯ octave the theme runs i, iiø⁷ (D♯, F♯, A, C♯), V⁷, i in bars 5–9, then cadences in G♯ minor.

B (13–24): the bass climbs

F♯ minor (iv) alternates with B⁷ and E, and in bars 21–24 Chopin's bass climbs while the right hand falls by half step, leaving the B♯°⁷ of bar 22 unresolved.

A′ and T (25–40): the theme, then the run

The theme returns, turns to F♯ minor, and a chromatic run with octaves in both hands carries it down to G♯, the dominant, in bar 40.

C (41–82): Largo, then Moderato cantabile

The Largo sets a slow tune in D♭ major. Its second idea, at bars 59–62 and again at 71–74, makes a full cadence in A♭, and bars 83–118 repeat bars 5–40.

Coda (119–138): C♯ major

From bar 129 the key is C♯ major and the bass carries the tune of section C, D♭ major respelled in sharps, closing V⁷ then I.

Study edition

Partial analysis: opening bars and a short note on each section. The full breakdown of every section is in the study edition of Fantaisie-Impromptu in C♯ minor.

Its place in the learning order is in Chopin for intermediate and returning adults, its level beside every other Chopin piece is in every Chopin piece by difficulty, and the left-hand pattern under it is measured in Chopin’s left-hand patterns, ranked by stretch.