A is a major, spelled A, C# and E. In Open G tuning (D2 G2 D3 G3 B3 D4) the easiest shape is x22222, which sits at fret 2, needs a barre across 5 strings at fret 2 and mutes 1 string. 12 positions for it are shown below, from the nut up to fret 14.
Notes and intervals
Note
A
C#
E
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.
x22222sits at fret 2, needs a barre across 5 strings at fret 2 and mutes 1 stringxx7657sits at fret 5, spans 2 frets and mutes 2 strings7676xxsits at fret 6, needs a barre across 3 strings at fret 6 and mutes 2 stringsx1414141414sits at fret 14, needs a barre across 5 strings at fret 14 and mutes 1 stringx91191011sits at fret 9, needs a barre across 3 strings at fret 9 and mutes 1 stringxx791011sits at fret 7, spans 4 frets and mutes 2 stringsx1411141411sits at fret 11, needs a barre across 4 strings at fret 11 and mutes 1 stringx14111410xsits at fret 10, spans 4 frets and mutes 2 stringsx2222xsits at fret 2, needs a barre across 4 strings at fret 2 and mutes 2 strings222222sits at fret 2 and needs a barre across 6 strings at fret 2xxx222sits at fret 2, needs a barre across 3 strings at fret 2 and mutes 3 strings22222xsits at fret 2, needs a barre across 5 strings at fret 2 and mutes 1 string
Keys A belongs to
A is diatonic to 24 of the 96 keys this app knows, playing a different role in each.