Chord reference
Diminished seventh
1 – ♭3 – ♭5 – ♭♭7 · example: Cdim7 = C – E♭ – G♭ – B𝄫
Three stacked minor thirds. It divides the octave evenly, so every inversion sounds like a root position.
Written as a formula it is 1 – ♭3 – ♭5 – ♭♭7: the degrees of the major scale it keeps, with any that are altered marked. On C that gives Cdim7 = C, E♭, G♭, B𝄫.
How it is built
- B𝄫minor
- G♭third
- E♭minor
- Croot
Play it on any root
The explorer starts on Cdim7. Strike it, then break it up one note at a time, then change the root — the shape on the keyboard is what stays the same. The other buttons are the chords one change away from this one.
The intervals above the root
| Chord tone | Interval above the root | Semitones | Note in Cdim7 |
|---|---|---|---|
| 1 | Perfect unison | 0 | C |
| ♭3 | Minor third | 3 | E♭ |
| ♭5 | Diminished fifth | 6 | G♭ |
| ♭♭7 | Diminished seventh | 9 | B𝄫 |
Inversions
The same notes can be stacked in any vertical order. The chord keeps its name; what changes is which note is in the bass. See chord inversions for why that matters, or press any notes into the chord identifier to have the chord and its inversion named for you.
| Position | Notes | Written as |
|---|---|---|
| Root position | C – E♭ – G♭ – B𝄫 | Cdim7 |
| First inversion | E♭ – G♭ – B𝄫 – C | Cdim7/E♭ |
| Second inversion | G♭ – B𝄫 – C – E♭ | Cdim7/G♭ |
| Third inversion | B𝄫 – C – E♭ – G♭ | Cdim7/B𝄫 |
This chord on every root
| Root | Symbol | Notes |
|---|---|---|
| C | Cdim7 | C – E♭ – G♭ – B𝄫 |
| D♭ | D♭dim7 | D♭ – F♭ – A𝄫 – C𝄫 |
| D | Ddim7 | D – F – A♭ – C♭ |
| E♭ | E♭dim7 | E♭ – G♭ – B𝄫 – D𝄫 |
| E | Edim7 | E – G – B♭ – D♭ |
| F | Fdim7 | F – A♭ – C♭ – E𝄫 |
| F♯ | F♯dim7 | F♯ – A – C – E♭ |
| G | Gdim7 | G – B♭ – D♭ – F♭ |
| A♭ | A♭dim7 | A♭ – C♭ – E𝄫 – G𝄫 |
| A | Adim7 | A – C – E♭ – G♭ |
| B♭ | B♭dim7 | B♭ – D♭ – F♭ – A𝄫 |
| B | Bdim7 | B – D – F – A♭ |