Banjo A7 chord (Open G)A seventh on the 5-string banjo: 2 2 2 2, and 5 more shapes

Frets, string 4 to string 1: 2 2 2 2 (first position) · 5th string completes it

1. String 4 (D): 2nd fret, index finger (barre), E
2. String 3 (G): 2nd fret, index finger (barre), A
3. String 2 (B): 2nd fret, index finger (barre), C♯
4. String 1 (D): 2nd fret, index finger (barre), E
5. String 5, the short g: open, G, in the chord

Sounds: E A C♯ E  ·  A7 is A, C♯, E, G (1 · 3 · 5 · ♭7)

The 5th string: the short g is the ♭7 of A7, so let it ring.

Up the neck: Barre 7 shape: 2 2 2 5 (2fr); F7 shape: 7 6 5 5 (5fr); E7 shape: 7 6 8 7 (6fr); D7 shape: 7 9 8 11 (7fr). Slide a shape up or down to play another chord of its kind.

With a capo: on the 2nd fret it’s 0 0 0 3 (frets counted from the capo), an open G7 shape. Spike the 5th string at the 7th fret to keep it in tune with the capo.

Open G tuning: gDGBD, the short 5th string first, then strings 4 to 1.