A dominant seventh
How to play A7 — Dominant seventh
A7 (Dominant seventh)A · C♯ · E · G
Guitar samples: Acoustic guitar — University of Iowa (via tonejs-instruments, CC-BY 3.0)
A dominant seventh — notes and structure
The A7 chord is a major triad with a flat seventh — the bluesy, restless chord that wants to resolve, central to blues and jazz.
The A7 dominant seventh consists of the notes A, C♯, E, G. Its interval structure is R–3–5–7 — the root, then each chord tone stacked above it. This is the same chord you see in the interactive finder above, drawn on the guitar fretboard with the root circled and every chord tone labelled.
A7 stacks a major third (C♯), a perfect fifth (E) and a minor seventh (G) above the root A.
The finder shows 2 ways to play A7 — an open-position shape reaching up to the 9th fret. 1 of them use a barre.
What key is A7 in?
Every note of A7 belongs to the scales below, so the chord sounds at home in each of these keys — the roman numeral is the degree it sits on.
- D major — the V chord
- B minor — the VII chord
Chords that go with A7
In D major, the chords built on the first, fourth and fifth degrees carry most songs — put A7 next to these:
Frequently asked questions
- What notes are in the A dominant seventh chord?
- The A7 chord contains the notes A, C♯, E, G. It is a major triad with a flat seventh — the bluesy, restless chord that wants to resolve, central to blues and jazz.
- How many ways can you play A7 on guitar?
- 2 voicings are shown on this page — from open position up the neck — each with its own fingering diagram and audio.
- Is A7 a hard chord to play?
- Some voicings use a barre, which takes practice, but the chord is very playable once that shape is comfortable.
- What key does A7 belong to?
- A7 fits D major (where it is the V chord), B minor (where it is the VII chord) — every note of the chord is in those scales.