F♯ Half-Diminished Seventh (Minor 7♭5)

Chord Tones: F♯ Half-Diminished Seventh (Minor 7♭5)

Symbol: ø7, m7♭5 — Formula: 1-♭3-♭5-♭7

Chord Notation

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

Inversions

Harmonic Function

The F♯ half diminished chord commonly functions as the tritone substitution in C major or tonic in F♯ 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 F♯ Half-Diminished Seventh (Minor 7♭5) specifically contains 4 notes: F♯, A, C, E (formula: 1-♭3-♭5-♭7). On piano, F#-rooted chords place the root on a black key, creating hand positions that many pianists find ergonomically comfortable for fast passages. Progressive rock, jazz fusion, and electronic music use F#-rooted chords to create unexpected harmonic shifts and chromatic modulations.

Common Progressions

The F♯ Half-Diminished Seventh (Minor 7♭5) frequently appears in these progression patterns (shown in Roman numeral notation relative to key):

• iihd7-V7-i
• viihd7-I

Songs Featuring the Half-Diminished Seventh (Minor 7♭5)

Well-known songs where the F♯ 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.

Scales Containing the F♯ Half-Diminished Seventh (Minor 7♭5)

These scales include the F♯ Half-Diminished Seventh (Minor 7♭5) as a diatonic or characteristic chord: