Piano chord · also written D♭m7♭5

C♯ Half-Diminished 7th Piano Chord (C♯m7♭5)

The C♯ Half-Diminished 7th chord on piano is made of the notes C♯, E, G and B. Bittersweet tension. Used as the ii chord in minor keys.

C♯ Half-Diminished 7th chord on a piano keyboard: C♯, E, G, B C4C5 C♯ E G B

C♯m7♭5 C♯ – E – G – B

Tap any key to hear it.

Name any chord from its keys in the chord finder →

What notes are in C♯ Half-Diminished 7th?

4 notes, built 1 – ♭3 – ♭5 – ♭7 up from C♯.

Notes
C♯ – E – G – B
Formula
1 – ♭3 – ♭5 – ♭7
Semitones from the root
0 – 3 – 6 – 10
Symbol
C♯m7♭5
Same keys as
D♭m7♭5 (D♭ – F♭ – G – C♭)
Chord type
Half-Diminished 7th, 4 notes

How to play C♯ Half-Diminished 7th on piano

  • Right hand: C♯ (1), E (2), G (3), B (5). Fingers 1 – 2 – 3 – 5, thumb on C♯.
  • Left hand: C♯ (5), E (3), G (2), B (1). Fingers 5 – 3 – 2 – 1, little finger on C♯.

Fingers are numbered 1 (thumb) to 5 (little finger) on both hands.

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C♯ Half-Diminished 7th inversions

Each inversion puts a different note of the chord in the bass. Written as a slash chord: C♯m7♭5/E, C♯m7♭5/G, C♯m7♭5/B.

C♯ Half-Diminished 7th root position on piano: C♯, E, G, B C♯ E G B
Root position C♯m7♭5 C♯ – E – G – B RH 1 – 2 – 3 – 5 · LH 5 – 3 – 2 – 1
C♯ Half-Diminished 7th 1st inversion on piano: E, G, B, C♯ E G B C♯
1st inversion C♯m7♭5/E E – G – B – C♯ RH 1 – 2 – 3 – 5 · LH 5 – 3 – 2 – 1
C♯ Half-Diminished 7th 2nd inversion on piano: G, B, C♯, E G B C♯ E
2nd inversion C♯m7♭5/G G – B – C♯ – E RH 1 – 2 – 3 – 5 · LH 5 – 3 – 2 – 1
C♯ Half-Diminished 7th 3rd inversion on piano: B, C♯, E, G B C♯ E G
3rd inversion C♯m7♭5/B B – C♯ – E – G RH 1 – 2 – 3 – 5 · LH 5 – 3 – 2 – 1

Progressions with C♯ Half-Diminished 7th

Press play: the chords move across the keyboard as they sound, voiced so your hand barely moves.

Minor ii–V–i

in B minor

  1. iiø7 C♯m7♭5
  2. V7 F♯7
  3. i Bm
Minor ii–V–i in B minor: C♯m7♭5, F♯7, Bm B C♯ E G

Leading-tone seventh

in D major

  1. ii7 Em7
  2. viiø7 C♯m7♭5
  3. Imaj7 Dmaj7
Leading-tone seventh in D major: Em7, C♯m7♭5, Dmaj7 B D E G

Can you find C♯ Half-Diminished 7th?

Tap the notes on the keyboard, then check. Six chords, starting with this one.

1 / 6 Tap the notes of C♯ Half-Diminished 7th (C♯m7♭5)

Score 0

Any octave, any order. Each key you tap plays.

Practice keyboard: tap the notes of the chord

What key is C♯ Half-Diminished 7th in?

The keys whose scale contains every note of C♯m7♭5, with the chord’s Roman numeral in each.

Major keys

  • D majorviiø7

Minor keys

  • B minoriiø7

C♯ Half-Diminished 7th chord FAQ

What notes are in the C♯ Half-Diminished 7th chord?

C♯ Half-Diminished 7th (C♯m7♭5) has 4 notes: C♯, E, G and B. Its formula is 1 – ♭3 – ♭5 – ♭7, counted up from C♯.

How do you play C♯ Half-Diminished 7th on the piano?

Put your right thumb on C♯ and play C♯, E, G and B with fingers 1 – 2 – 3 – 5. With the left hand, use fingers 5 – 3 – 2 – 1, little finger on C♯.

Is C♯ Half-Diminished 7th the same as D♭ Half-Diminished 7th?

On the piano, yes: D♭m7♭5 (D♭, F♭, G, C♭) uses exactly the same keys as C♯m7♭5 (C♯, E, G, B). Which name is used depends on the key of the piece; C♯m7♭5 is the more common spelling.

What are the inversions of C♯ Half-Diminished 7th?

1st inversion: E, G, B, C♯ (C♯m7♭5/E). 2nd inversion: G, B, C♯, E (C♯m7♭5/G). 3rd inversion: B, C♯, E, G (C♯m7♭5/B).

What key is C♯ Half-Diminished 7th in?

C♯m7♭5 belongs to D major (viiø7) and B minor (iiø7).

Other C♯ chords

Half-Diminished 7th chords on every root

Piano chord chart: all 264 chords Open C♯m7♭5 in the chord finder Free PDF chord chart Play it on the virtual piano