Bbm7b5 Chord (Bb half-diminished) on Guitar
Bbm7b5 (Bb half-diminished (minor 7 flat 5)) is made of the notes Bb – Db – Fb – Ab. The easiest guitar fingering is x12120 (low E to high e; x = muted, 0 = open). It uses a barre, so it is more demanding than an open chord. Expect it to take some practice to sound clean.
Easiest shape
Alternative shape
How to play Bbm7b5
- Press the 5th string (A) at fret 1 (Bb).
- Press the 4th string (D) at fret 2 (Fb).
- Press the 3rd string (G) at fret 1 (Ab).
- Press the 2nd string (B) at fret 2 (Db).
- Play the 1st string (high e) open (Fb).
- Do not play the 6th string (low E).
| String | Fret | Note | Role |
|---|---|---|---|
| 6th string (low E) | x (mute) | - | |
| 5th string (A) | 1 | Bb | R |
| 4th string (D) | 2 | Fb | b5 |
| 3rd string (G) | 1 | Ab | b7 |
| 2nd string (B) | 2 | Db | b3 |
| 1st string (high e) | 0 (open) | Fb | b5 |
What is a Bb half-diminished (minor 7 flat 5) chord?
A half-diminished (minor 7 flat 5) chord is a diminished triad with a minor seventh. It is the seventh-degree chord of a major scale.
Notes and formula. Bbm7b5 contains Bb, Db, Fb, Ab. Counted from the root Bb, that is R (root), b3 (minor 3rd), b5 (diminished 5th), b7 (minor 7th). It is also written A#m7b5; the two names sound identical and the name used depends on the key of the song.
Sound. Moody and sophisticated, less harsh than a fully diminished chord.
Where it is used. Used constantly in jazz as the ii chord of a minor ii-V-i progression, and in many ballads.
Tips for playing Bbm7b5
It often shares its shape with a minor 6th chord. Learn them as pairs.
Common mistake: Calling it a diminished chord. A fully diminished 7th has a diminished (double-flat) seventh instead.
Keys that contain Bbm7b5
Bbm7b5 is a diatonic chord, meaning it occurs naturally without accidentals, in these keys:
Try it in a progression: browse chord progressions for every key.
Related chords
Bbm7b5 chord FAQ
What notes are in a Bbm7b5 chord?
Bbm7b5 (Bb half-diminished (minor 7 flat 5)) contains the notes Bb, Db, Fb, Ab. The formula is R–b3–b5–b7 relative to the root Bb.
How do you play Bbm7b5 on guitar?
The most common shape for Bbm7b5 is x12120, read from the low E string to the high e string (x = muted, 0 = open, numbers = frets). It uses a barre, so it is more demanding than an open chord. Expect it to take some practice to sound clean.
Is Bbm7b5 an easy guitar chord?
It is rated intermediate. It uses a barre, so it is more demanding than an open chord. Expect it to take some practice to sound clean.
Is Bbm7b5 the same as A#m7b5?
Yes. Bb and A# are enharmonic: they are the same pitch with different names, so Bbm7b5 and A#m7b5 sound identical on guitar. The name used depends on the key of the song.
Which keys contain Bbm7b5?
Bbm7b5 is a diatonic chord in B major (vii°), Ab minor (ii°).
Get one useful guitar tip a week
New chord guides, practice ideas and app updates. No spam, unsubscribe anytime.