Gdim is a diminished, spelled G, Bb and Db. In Ukulele (low G) tuning (G3 C4 E4 A4) the easiest shape is 0131, which sits at fret 1, needs a barre across 3 strings at fret 1 and lets 1 string ring open. 12 positions for it are shown below, from the nut up to fret 13.
Notes and intervals
Note
G
Bb
Db
Interval
1P
3m
5d
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.
0131sits at fret 1, needs a barre across 3 strings at fret 1 and lets 1 string ring open010910sits at fret 9, spans 1 fret and lets 1 string ring open076xsits at fret 6, spans 1 fret, lets 1 string ring open and mutes 1 string0764sits at fret 4, spans 3 frets and lets 1 string ring open0131513sits at fret 13, needs a barre across 3 strings at fret 13 and lets 1 string ring open12131513sits at fret 12 and spans 3 frets3764sits at fret 3 and spans 4 frets0109xsits at fret 9, spans 1 fret, lets 1 string ring open and mutes 1 string3131sits at fret 1 and needs a barre across 3 strings at fret 1313xsits at fret 1, spans 2 frets and mutes 1 stringx131sits at fret 1, needs a barre across 3 strings at fret 1 and mutes 1 stringx764sits at fret 4, spans 3 frets and mutes 1 string
Keys Gdim belongs to
Gdim is diatonic to 8 of the 96 keys this app knows, playing a different role in each.