F#m7b5

F# Half-dim 7

Octaves

Musical context

How the chord relates to the scale, mode, key and progression.

Theory

General info

Full name
F# Half-dim 7
Symbol
F#m7b5
Root
F#
Quality
Half-dim 7

Chord notes

1F#root
b3Aminor 3rd
b5Cdim 5th
b7Eminor 7th

Functions & resolutions

Typical function in key
vii°Leading tone (vii°)G major
Stability / tension
High tension — pulls toward the dominant
Most common resolutions
Unstable degrees
2G#
b3A
resolves down to the 2nd
4B
b5C
resolves inward to the 4th
4B
b7E
resolves down to the resolution tonic
Main resolution
F#m7b5source
B7B Dominant 7
Half-diminished F#m7b5 typically acts as ii in minor, resolving to the dominant (B7), which then leads to the tonic.
Other resolutions
F#m7b5source
Deceptive resolution
EmE Minor
The half-diminished chord can bypass the dominant and resolve directly to the minor tonic — a plagal turn in minor.
F#m7b5source
No resolution needed
In the Locrian mode, a half-diminished chord can function as the tonic, requiring no resolution.
F#m7b5source
Jazz reharmonization
Am6A Minor 6
In jazz, ø7 is common in ii-V-i progressions but can be substituted with iv6, sharing the same notes.
F#m7b5source
Functional resolution
DD Major
Besides moving to the dominant, the half-diminished chord can resolve to bVI — creating a Phrygian color.

Features

Character
Half-diminished, unstable
Characteristic interval
Diminished 5th (b5)
Description
The diminished fifth creates instability, the minor seventh softens it. Less tense than fully diminished.
Application
  • iiø7 in natural minor
  • Jazz ii–V in minor
  • Unstable predominant sonorities

Voicing & structure

Root position

v1F#(F#4)Bass
root
v2A(A4)m3from F#
v3C(C5)m3from A
v4E(E5)M3from C

Harmony

Compatible scales

All chord tones are contained in these scales — use them for improvisation.

This chord on guitar 🎸

See how F#m7b5 looks on guitar.

Explore

Circle of fifths

Highlighted major keys contain this chord among their diatonic harmonies.

CAmGEmDBmAF#mEC#mBG#mF#D#mDbBbmAbFmEbCmBbGmFDmF#major
Relative key
Dominant
Subdominant
Key signature
6 sharps (F#, C#, G#, D#, A#, E#)

Practice

Keyboard Trainer

Reinforce it in practice — play and name notes on the interactive keyboard.

Open Trainer

Test yourself

(Press any key to start)

Frequently Asked Questions