guitar chord
B♭13
Seven notes in theory and four or five in anyone’s hands: root, third, seventh and thirteenth carry it.
Written the other way round it is A♯13 — the same twelve keys on a piano, a different piece of notation.
Every fingering that fits a hand
630064
moderate
650064
moderate · no 9
x10014
easy · no 5
630034
moderate · no 5
x10034
easy · no 5, 9
What is true of it
B♭13 is B♭, D, F, A♭, C and G — 1, 3, 5, b7, 9 and 13 counted from B♭.
On an instrument that cannot reach all 6, the 5, 9 and 1 go first, in that order.
The easiest of the 5 fingerings below is 630064: 4 fingers, held at the 3rd fret.
None of them uses an open string, so this chord moves up the neck unchanged — the same shape 1 fret higher is the chord a semitone above.
Where its notes are on the neck
The brass dots are B♭, the root. Everything else is a chord tone with its degree printed in it.
With a different note underneath
B♭13/D
x50064
B♭13/F
110014
B♭13/A♭
410011
An inversion is the same chord with a different note lowest. The name changes to a slash name because the bass is what a listener hears as the foundation.