The midpoint between the open keys and the barre-heavy ones.
See how all seven chords sit together, and hear what makes each degree do its job.
Open A Major in the Studio →The key of A Major contains A, Bm, C#m, D, E, F#m, G#dim. In Roman numerals that's I, ii, iii, IV, V, vi, vii° — the tonic (A) is home, and the dominant (E) creates the tension that resolves back to it.
Because its three primary chords — A, D and E — are all easy open shapes that sit naturally under the hand, and the key's open A string gives riffs a strong low anchor. It's a comfortable place to play loud rhythm guitar, which is exactly what blues and rock ask for.