B Diminished Seventh Chord
Chord Tones: B Diminished Seventh Chord
Symbol: dim7, °7 — Formula: 1-♭3-♭5-𝄫7
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | B | 493.883 Hz |
| ♭3 | D | 293.665 Hz |
| ♭5 | F | 349.228 Hz |
| 𝄫7 | G# | 415.305 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | Bdim7 |
| All Common Symbols | dim7, °7 |
| Interval Formula | 1-♭3-♭5-𝄫7 |
| Harmonic Category | tense |
Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.
Inversions
| Inversion | Notes (low to high) | Bass Note | Slash Notation |
|---|---|---|---|
| Root Position | B – D – F – G# | B | B Diminished Seventh Chord |
| First Inversion | D – F – G# – B | D | B Diminished Seventh Chord/D |
| Second Inversion | F – G# – B – D | F | B Diminished Seventh Chord/F |
| Third Inversion | G# – B – D – F | G# | B Diminished Seventh Chord/G# |
Harmonic Function
The B diminished seventh chord commonly functions as the leading tone (vii) in C major or dominant (V) in E major. Its harmonic role varies by key — in major keys it provides extended harmonic tension.
The diminished seventh chord consists of four equally-spaced minor thirds, creating a symmetrical, highly dissonant chord. It is used as a dramatic pivot chord and in chromatic passing harmony.
Common Progressions
The B Diminished Seventh Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
vii°7-I#iv°7-V
Songs Featuring the Diminished Seventh Chord
Well-known songs where the B Diminished Seventh Chord — or this chord type — plays a prominent role:
- While My Guitar Gently Weeps – Beatles
- Georgia on My Mind – Ray Charles
- Sophisticated Lady – Duke Ellington
Tuning Frequencies Across Temperaments
Frequencies shown at A=440 Hz. View full temperament data for any note.
| Note | Equal Temp. | Pythagorean | Just Intonation |
|---|---|---|---|
| B | 493.883 Hz | 495.000 Hz | 490.548 Hz |
| D | 293.665 Hz | 293.332 Hz | 294.329 Hz |
| F | 349.228 Hz | 347.654 Hz | 348.834 Hz |
| G# | 415.305 Hz | 417.657 Hz | 418.601 Hz |
Scales Containing the B Diminished Seventh Chord
These scales include the B Diminished Seventh Chord as a diatonic or characteristic chord: