Root, third and seventh: the guide tones fix the quality, so the fifth is dropped. That is what leaves a string free, so pick a tension to put on top.
Em7b5 is E, G, Bb and D — Em7 with the fifth lowered a semitone.
It sounds hollow, and unmistakably going somewhere. Almost always the first chord of a minor ii–V–i, so it walks straight into an altered dominant.

| E | G | Bb | D |
|---|---|---|---|
| 1 | ♭3 | ♭5 | ♭7 |
Pre-dominant — the ii of a minor key.
Also written Eø, Eø7, Em7-5, Em7(b5) or E half diminished. The same chord either way; which spelling you meet depends on who wrote the chart.
Root, third and seventh. The third and seventh, the guide tones, are what make the chord major, minor or dominant, so the fifth can go: it says nothing the symbol needs.
Three notes means a spare string, which is the real point. Put a tension on it.
Em7b5 has 7 of them, on the bottom four strings, the top four strings, strings 5-3-2-1, strings 6-4-3-2 and the middle four strings, from the 2nd fret up to the 11th — all in one inversion, so the bass note never moves. The one to learn first is the E shape at the 3rd fret, which is the easiest grip here.
Start with x7878x — no barre. 1 of the 9 shapes here sits in open position. 5 of the 9 need a barre. Together they cover the neck from the 1st fret to the 15th.
| Frets | Where | Bass | Top | Hand |
|---|---|---|---|---|
| 012333 | open position | E, root position | G | barred |
| xx2333 | 2nd fret | E, root position | G | barred |
| x75756 | 5th fret | E, root position | Bb | all fretted |
| x7878x | 7th fret | E, root position | G | all fretted |
| x-x-8-9-8-10 | 8th fret | Bb, 2nd inversion | D | all fretted |
| 12-x-x-12-11-10 | 10th fret | E, root position | D | all fretted |
| 12-x-12-12-11-x | 11th fret | E, root position | Bb | barred |
| 12-13-14-12-15-12 | 12th fret | E, root position | E | barred |
| x-x-14-15-15-15 | 14th fret | E, root position | G | barred |
The same notes rebuilt from scratch give 15 drop 2, 10 drop 3 and 6 open string voicings, each on its own page.
Tensions. A shell of Em7b5, root, third and seventh, leaves a string free, and the tones that belong over it are the 11 (A) and the b13 (C).
Em7b5 is the ii of D minor, which is where it is nearly always found: half-diminished, then an altered dominant, then the minor tonic.
In which keys. Every note of Em7b5 belongs to D minor (the ii°, the supertonic) and F major (the vii°, the leading tone).
Every note of Em7b5 is in E blues, E locrian, E altered and E half-whole diminished.
Change one note of Em7b5 and you have Edim (drop the flat seventh), Edim7 (the flat seventh becomes a sixth), Em7 (the flat fifth becomes a fifth), EmMaj7b5 (the flat seventh becomes a major seventh), E7b5 (the minor third becomes a major third) or Em/D (the flat fifth becomes a fifth).
Em7b5 is a diminished chord — root, minor third, flat fifth. Diminished and half-diminished chords on every root.
On Em7b5’s sound and use this page follows Mark Levine, The Jazz Theory Book (Sher Music, 1995). The shapes and the derived voicings come from different places, and both are explained in where the chords and the theory come from.
Shows each chord the way this style would voice it, and marks which of its alternatives belong to the idiom.