B Half-Diminished Seventh (Minor 7♭5)
Chord Tones: B Half-Diminished Seventh (Minor 7♭5)
Symbol: ø7, m7♭5 — Formula: 1-♭3-♭5-♭7
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | B4 | 493.883 Hz |
| ♭3 | D4 | 293.665 Hz |
| ♭5 | F4 | 349.228 Hz |
| ♭7 | A4 | 440.000 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | Bø7 |
| All Common Symbols | ø7, m7♭5 |
| Interval Formula | 1-♭3-♭5-♭7 |
| Harmonic Category | dissonant |
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 | B4 – D4 – F4 – A4 | B | B Half-Diminished Seventh (Minor 7♭5) |
| First Inversion | D4 – F4 – A4 – B4 | D | B Half-Diminished Seventh (Minor 7♭5)/D |
| Second Inversion | F4 – A4 – B4 – D4 | F | B Half-Diminished Seventh (Minor 7♭5)/F |
| Third Inversion | A4 – B4 – D4 – F4 | A | B Half-Diminished Seventh (Minor 7♭5)/A |
Harmonic Function
The B half diminished 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 stable harmonic grounding.
The half-diminished chord (minor seven flat five) combines a diminished triad with a minor seventh. It is the ii chord in minor keys and an essential sound in jazz and classical harmony. The B Half-Diminished Seventh (Minor 7♭5) specifically contains 4 notes: B, D, F, A (formula: 1-♭3-♭5-♭7). On guitar, B-rooted chords are typically played as barre chords at the second or seventh fret, and on piano they use a comfortable mix of black and white keys. K-pop, J-pop, and modern R&B productions frequently feature B-rooted chords, chosen for how the key sits within typical vocal ranges.
Common Progressions
The B Half-Diminished Seventh (Minor 7♭5) frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
Songs Featuring the Half-Diminished Seventh (Minor 7♭5)
Well-known songs where the B Half-Diminished Seventh (Minor 7♭5) — or this chord type — plays a prominent role:
- Autumn Leaves (minor ii chord) – jazz standard
- Beautiful Love – jazz standard
- Solar – Miles Davis
Tuning Frequencies Across Temperaments
Frequencies shown at A=440 Hz. View full temperament data for any note.
| Note | Equal Temp. | Pythagorean | Just Intonation |
|---|---|---|---|
| B4 | 493.883 Hz | 495.000 Hz | 490.548 Hz |
| D4 | 293.665 Hz | 293.332 Hz | 294.329 Hz |
| F4 | 349.228 Hz | 347.654 Hz | 348.834 Hz |
| A4 | 440.000 Hz | 440.000 Hz | 436.043 Hz |
Scales Containing the B Half-Diminished Seventh (Minor 7♭5)
These scales include the B Half-Diminished Seventh (Minor 7♭5) as a diatonic or characteristic chord: