C-7b9#11 Minor 7th

The C-7b9#11 chord is built from the notes C – Eb – G – Bb – Db – F#.

Piano sound loads on first tap.

Also known as

Cm7b9#11Cmi7(b9#11)Cmi7b9#11

Chord tones, one by one

CRoot

Root

The fundamental note the chord is built on — C.

EbThird

Minor third

Three semitones — makes the chord minor (darker, sadder).

GFifth

Perfect fifth

Seven semitones — the most stable interval, reinforces the root.

BbSeventh

Minor seventh (♭7)

Ten semitones — the dominant/minor seventh. Adds bluesy tension (7, m7).

DbExtension

Flat ninth (♭9)

A ♭9 — sharp, dissonant tension typical of altered dominant chords.

F#Extension

Sharp eleventh (♯11)

A ♯11 — the bright, floating Lydian color.

🎹 Modal analysis

This chord is so rich it doesn't fit a single scale: it's a polychord (an “upper structure”) that stacks tensions from several scales at once. It doesn't work like a dominant that “wants” to resolve — it's pure color: picture one triad floating over an unrelated bass, the kind of sound used in reharmonization and modal passages. To make sense of it, follow the note-by-note breakdown above.

🎸 Genres

Modern jazz · Fusion · Film & TV scoring · Impressionism

-7b9#11 in every key

More C chords