Gm7♭5 chord on guitar
The Gm7♭5 chord, or G half-diminished, stacks 4 notes on G: G, B♭, D♭ and F. Musicians write its formula 1 ♭3 ♭5 ♭7.
Notes and intervals of Gm7♭5
Each note of Gm7♭5 has a job. Counted from the root, you get root (G), minor 3rd (B♭), diminished 5th (D♭) and minor 7th (F). Change one of these intervals and you get a different chord, which is why the formula 1 ♭3 ♭5 ♭7 is worth memorising rather than the shape alone.
| Degree | Interval | Note |
|---|---|---|
| 1 | root | G |
| ♭3 | minor 3rd | B♭ |
| ♭5 | diminished 5th | D♭ |
| ♭7 | minor 7th | F |
How to play Gm7♭5 on guitar
Start with the first diagram: 3 x x 3 2 1, read from the 6th string (low E) to the 1st string (high E). Your lowest note is G. The next positions give the same notes in a different order, which is useful when you want Gm7♭5 to sit closer to the surrounding chords.
This is a barre or movable shape: keep your index finger straight and close to the fret, and press with the side of the finger rather than the flat pad.
Which keys use Gm7♭5?
You find Gm7♭5 as a diatonic chord in A flat major (viiø7). The most common case is A flat major, where it plays the role of viiø7.
Scales to play over Gm7♭5
These scales share every note of Gm7♭5: G blues scale and G Locrian mode. G blues scale is the safest choice; the others add more colour.
About half-diminished chords
A diminished triad plus a minor seventh: 1 ♭3 ♭5 ♭7. Called half-diminished (ø), it is dark and unsettled but softer than a full diminished seventh, because its seventh is minor. It sounds like a question, a sigh that wants to move on. For example Bm7♭5: B D F A.
Its main home is the minor ii-V-i: iiø7 V7 i (for example Bm7♭5 E7 Am). In a major key it sits on viiø7. Jazz, bossa nova and neo-soul use it constantly, and it can also stand in for ivm6 in a minor key, since both chords share the same notes (for example Bm7♭5 and Dm6).
Two movable shapes cover most needs: root on the 5th string (for example Bm7♭5 x2323x) and root on the 6th string with the 5th string muted (for example Bm7♭5 7x776x). Learn each one together with the 7 chord and the minor chord that follow it in a minor ii-V-i, in the same area of the neck.
m7♭5 is not dim7: dim7 has a diminished seventh (A♭ in Bdim7), m7♭5 a minor seventh (A in Bm7♭5). It is not m6 either, although the two share notes: the bass decides. And remember that m7♭5, m7(♭5), -7♭5 and ø7 are all names for the same chord.
Frequently asked questions
What notes are in the Gm7♭5 chord?
Gm7♭5 (G half-diminished) contains G, B♭, D♭ and F. In intervals: root (G), minor 3rd (B♭), diminished 5th (D♭) and minor 7th (F).
How do you play Gm7♭5 on guitar?
The easiest shape is 3 x x 3 2 1, from the low E string to the high E string. This page shows 3 positions with finger numbers.
What scale goes with Gm7♭5?
G blues scale fits Gm7♭5 best. Other scales that contain all its notes: G Locrian mode.
What key is Gm7♭5 in?
Gm7♭5 belongs to A flat major (viiø7). In A flat major it is the viiø7 chord.
Related
Ready to go further than the chart?
The free GuitarHarmony workshop shows every scale on the whole neck, names any chord you play and builds progressions with you. Free account, no card.