Gm7b5 Chord on Guitar
Gm7b5 = G – A# – C# – F (Root, Minor 3rd, Tritone, Minor 7th)
Gm7b5, or half-diminished, lowers the fifth of Gm7 by a half step, landing between the smooth consonance of a plain minor seventh and the fully unstable dissonance of a diminished seventh — diminished in one respect, not all the way, exactly as the name suggests.
G-Bb-Db-F: root, minor third, diminished fifth, and minor seventh. That lowered fifth on an otherwise ordinary minor-seventh structure is the signature sound of the ii chord in minor-key jazz harmony — Gm7b5 is exactly the chord a minor ii-V-i progression needs when the key center is F minor, replacing the plain minor seventh a major-key ii-V would use with this darker, more tension-laden version.
Fingerings
Barre (3rd fret)
How to Practice It
This shape uses a slightly different finger arrangement than the straightforward major or minor barres in this family since the altered fifth changes the muted or repositioned strings — take it slowly, isolating the fifth's new position before strumming the whole chord at tempo. Practice it inside a ii-V-i in F minor (Gm7b5 – C7 – Fm) to hear why this chord exists rather than a plain Gm7: the lowered fifth intensifies the pull toward the dominant that follows.
Common Progressions
- Gm7b5 – C7 – Fm (ii – V7 – i, the classic minor-key jazz turnaround)
- Gm7b5 – C7 – Fm – Bbm (a fuller minor ii-V-i moving on to iv)
- Eb – Gm7b5 – C7 (a color move using the half-diminished chord as an unsettled pivot before resolving)
- Fm – Gm7b5 – C7 – Fm (i – ii – V7 – i, a compact minor-key loop)
FAQ
- What does 'half-diminished' mean for Gm7b5?
- It shares the diminished triad's lowered fifth but keeps a regular minor seventh rather than the fully diminished seventh a true dim7 chord uses, landing it harmonically between the two in terms of tension.
- Where does Gm7b5 typically appear?
- As the ii chord in a minor-key ii-V-i progression — most commonly in F minor, where it leads into C7 and then resolves to Fm, mirroring the role a plain minor seventh ii chord plays in major-key jazz harmony.
- How does Gm7b5 differ from Gdim7?
- Gdim7 lowers both the fifth and the seventh, giving a fully symmetrical, more starkly tense chord, while Gm7b5 only lowers the fifth and keeps an ordinary minor seventh, making it noticeably less dissonant.
- Is Gm7b5 common outside jazz contexts?
- It appears far more often in jazz and jazz-influenced writing than in straightforward pop or rock, since minor ii-V-i progressions are themselves a specifically jazz harmonic device.
- Is Gm7b5 hard to fret?
- It's a somewhat less intuitive shape than the plain major or minor barres since the altered fifth changes the finger pattern, but it's compact enough that it becomes comfortable with focused practice.
Gm7b5 on other instruments: Gm7b5 on Piano. Related: how chords are built, chord finder.