— A diminished 7th triad —

D# diminished 7 chord

Notes: D# · F# · A · C

Practice this chord in the trainer →

D♯°7 — D♯, F♯, A, C — is the vii°7 of E minor (and E major when borrowing from parallel minor). All three intervals are minor thirds, making the chord fully symmetric. D♯°7 is enharmonically equivalent to F°7, A°7, and C°7 (an altered dominant context).

Intervals

The D# diminished 7 chord stacks two thirds on the root. Each interval and its size in semitones:

  • D#F#minor 3rd3 semitones
  • F#Aminor 3rd3 semitones
  • ACdiminished 7th9 semitones

On the keyboard

Each note of the D# diminished 7 chord highlighted on a piano. Pitch class is what matters — any octave works.

On the guitar

One voicing of the D# diminished 7 chord on a six-string guitar fretboard.

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Common mistakes

D♯°7 mixes two sharps (D♯, F♯) with two naturals (A, C). The mixed-accidental signature is part of its visual identity. In jazz, the chord is sometimes written E♭°7 instead — same pitches, but the flat-side spelling. Both are valid depending on surrounding harmony.

In context

D♯°7 → E minor is the leading-tone cadence in E minor. As an altered V/V/V (chains of secondary dominants), the chord pivots through multiple minor keys in chromatically modulating music. The "diminished sequence" in classical literature often climbs through D♯°7 → E°7 → F°7 → ... before resolving.

Drill it

The D# diminished 7 chord is one of 48 in the Chord Trainer. Open the full trainer to practice it alongside related chords with timing and best-time tracking.

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Related

Frequently asked

What notes are in a D♯ diminished 7 chord?
D♯°7 contains four notes: D♯ (root), F♯ (minor third), A (diminished fifth), and C (diminished seventh).
How does D♯°7 resolve?
In E minor: D♯ rises to E, F♯ holds or rises to G, A holds, and C falls to B. Every voice moves by half-step or whole-step to a chord tone of E minor.
Is D♯°7 the same as E♭°7?
Enharmonically yes — same four pitches. D♯°7 spells the chord in sharp-key contexts (E minor); E♭°7 (E♭-G♭-B♭♭-D♭♭) is essentially never written because of double flats.
Where does D♯°7 appear in music?
In E-minor and E-major leading-tone cadences. Mendelssohn's "Italian" Symphony finale (in F♯ minor) uses adjacent dim7 chords; D♯°7 also appears in jazz progressions through E minor.