C is a major, spelled C, E and G. In Open G tuning (D2 G2 D3 G3 B3 D4) the easiest shape is x55555, which sits at fret 5, needs a barre across 5 strings at fret 5 and mutes 1 string. 12 positions for it are shown below, from the nut up to fret 13.
Notes and intervals
Note
C
E
G
Interval
1P
3M
5P
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.
x55555sits at fret 5, needs a barre across 5 strings at fret 5 and mutes 1 string202012sits at fret 1, spans 1 fret and lets 2 strings ring openx52055sits at fret 2, spans 3 frets, lets 1 string ring open and mutes 1 string100109xxsits at fret 9, spans 1 fret, lets 1 string ring open and mutes 2 strings1001098xsits at fret 8, spans 2 frets, lets 1 string ring open and mutes 1 string1401401314sits at fret 13, spans 1 fret and lets 2 strings ring openx014121314sits at fret 12, spans 2 frets, lets 1 string ring open and mutes 1 string1001401314sits at fret 10, spans 4 frets and lets 2 strings ring openx02012sits at fret 1, spans 1 fret, lets 2 strings ring open and mutes 1 string20201xsits at fret 1, spans 1 fret, lets 2 strings ring open and mutes 1 stringx5555xsits at fret 5, needs a barre across 4 strings at fret 5 and mutes 2 stringsx55055sits at fret 5, needs no stretch at all, lets 1 string ring open and mutes 1 string
Keys C belongs to
C is diatonic to 24 of the 96 keys this app knows, playing a different role in each.