Barre chord
fret 1, A shapex13121
B♭m7 is the B♭ minor 7 chord. Its notes are B♭, D♭, F and A♭. It is the same chord as A♯m7. A softer minor sound. Useful in soul, pop and ii–V–I progressions.
x13121
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Numbers show frets from the low E string to the high e string; x means don't play that string.
B♭m7 is the ii7 chord in A♭ major, the iii7 chord in G♭ major and the vi7 chord in D♭ major. That makes it a natural fit in songs written in those keys.
Every B♭, D♭, F and A♭ on the first 12 frets. The filled dots are the root, B♭. Build your own shape from any nearby group.
Other B♭ chords
Other minor 7 chords