Bb7 is a dominant seventh, spelled Bb, D, F and Ab. In Ukulele (low G) tuning (G3 C4 E4 A4) the easiest shape is 3545, which sits at fret 3 and spans 2 frets. 12 positions for it are shown below, from the nut up to fret 13.
Notes and intervals
Note
Bb
D
F
Ab
Interval
1P
3M
5P
7m
12 ways to play it
Ordered by how hard they are to fret, easiest first, one per position on the neck. Fret numbers are relative to the position marked beside each grid.
3545sits at fret 3 and spans 2 frets1211sits at fret 1 and needs a barre across 4 strings at fret 1324xsits at fret 2, spans 2 frets and mutes 1 string7868sits at fret 6 and spans 2 fretsx101011sits at fret 10, needs a barre across 2 strings at fret 10 and mutes 1 string13141313sits at fret 13 and needs a barre across 4 strings at fret 137865sits at fret 5 and spans 3 frets15141311sits at fret 11 and spans 4 frets7101011sits at fret 7 and spans 4 frets3241sits at fret 1 and spans 3 frets3245sits at fret 2 and spans 3 frets10101011sits at fret 10 and needs a barre across 3 strings at fret 10
Keys Bb7 belongs to
Bb7 is diatonic to 8 of the 96 keys this app knows, playing a different role in each.