Chords in the key of G major
The chord chart below lists all the common traids and 
four note extended chords belonging to the key of G major. 
Roman numerals indicate each chords position relative to 
the scale.

G major scale notes: G A B C D E F#
Major key chord sequence: Maj min min Maj Maj min dim
I	ii	iii	IV	V	vi	vii
Gmaj	Amin	Bmin	Cmaj	Dmaj	Emin	F#dim
Gmaj7	Amin7	Bmin7	Cmaj7	D7	Emin7	F#m7b5
Common chord progressions in G major
I - IV - V	G - C - D
I - vi - IV - V	G - Em - C - D
ii - V - I	Am - D7 - GM7