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

DegreeNoteFrequency (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 TypeSymbol / Value
Lead Sheet SymbolBø7
All Common Symbolsø7, m7♭5
Interval Formula1-♭3-♭5-♭7
Harmonic Categorydissonant

Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.

Inversions

InversionNotes (low to high)Bass NoteSlash 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:

Tuning Frequencies Across Temperaments

Frequencies shown at A=440 Hz. View full temperament data for any note.

NoteEqual Temp.PythagoreanJust 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: