semicord

Bbm7 Bb minor seventh chord

Notes
Bb Db F Ab
Formula
1 b3 5 b7
Semitones
0 3 7 10 above the root
Also written
A#m7 (A# C# E# G#)
Other symbols
Bbmin7, Bb−7

Bb to Db is a minor third (3 semitones), Db to F is a major third (4 semitones), F to Ab is a minor third (3 semitones). A minor triad plus a minor seventh (Ab). With Db in the bass the same four notes are read as Db6.

Bbm7 on the piano

C4D4E4F4G4A4B4C5D5E5F5G5A5B5C#4Eb4F#4Ab4Bb4Db5Eb5F#5Ab5Bb5C4BbC5DbFAb

Root position from Bb4: Bb4, Db5, F5, Ab5. Middle C is C4.

Bbm7 on the guitar

Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has Bb as its lowest note.

×BbBbFFAbAbDbDbFF
A-shape barre, root on the A string at fret 1
x 1 3 1 2 1 (low E to high e)
Sounds Bb2 F3 Ab3 Db4 F4
6frBbBbFFAbAbDbDbFFBbBb
E-shape barre, root on the E string at fret 6
6 8 6 6 6 6 (low E to high e)
Sounds Bb2 F3 Ab3 Db4 F4 Bb4

The barre shapes are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play minor seventh chords on other roots.

Inversions of Bbm7

An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.

PositionNotes, bass firstNamedListen
Root positionBb Db F AbBbm7
1st inversionDb F Ab BbDb6 (also read as Bbm7/Db)
2nd inversionF Ab Bb DbBbm7/F
3rd inversionAb Bb Db FBbm7/Ab

Where Bbm7 fits

Bbm7 is ii7 in Ab major, iii7 in Gb major, vi7 in Db major. As ii7 it is the first chord of the ii–V–I that ends countless jazz and pop phrases: Bbm7 → Eb7 → Abmaj7.