C7 is a dominant seventh, spelled C, E, G and Bb. In Open G tuning (D2 G2 D3 G3 B3 D4) the easiest shape is x5535x, which sits at fret 3, spans 2 frets and mutes 2 strings. 12 positions for it are shown below, from the nut up to fret 13.
Notes and intervals
Note
C
E
G
Bb
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.
x5535xsits at fret 3, spans 2 frets and mutes 2 stringsx02312sits at fret 1, spans 2 frets, lets 1 string ring open and mutes 1 string1008988sits at fret 8, needs a barre across 4 strings at fret 8 and lets 1 string ring open10010911xsits at fret 9, spans 2 frets, lets 1 string ring open and mutes 1 stringx55558sits at fret 5, needs a barre across 4 strings at fret 5 and mutes 1 stringx52352sits at fret 2, needs a barre across 4 strings at fret 2 and mutes 1 stringx014151314sits at fret 13, spans 2 frets, lets 1 string ring open and mutes 1 string1001401114sits at fret 10, spans 4 frets and lets 2 strings ring openx12141513xsits at fret 12, spans 3 frets and mutes 2 stringsx32012sits at fret 1, spans 2 frets, lets 1 string ring open and mutes 1 string20231xsits at fret 1, spans 2 frets, lets 1 string ring open and mutes 1 string23201xsits at fret 1, spans 2 frets, lets 1 string ring open and mutes 1 string
Keys C7 belongs to
C7 is diatonic to 8 of the 96 keys this app knows, playing a different role in each.