Chord Functions
Understanding the role each chord plays in a key
In tonal music, every chord in a key has a specific function or role. These functions are generally categorized into three groups: Tonic (Rest), Subdominant (Movement away), and Dominant (Tension leading back).
I
Tonic
The home base. Feels stable, resolved, and at rest. Key center.
ii
Supertonic
Predominant. Leads to V or sometimes back to I (plagal). Minor in major keys.
iii
Mediant
Halfway between tonic and dominant. Can substitute for I or lead to vi.
IV
Subdominant
Predominant. Strong movement away from tonic. Often leads to V.
V
Dominant
Tension. Wants to resolve back to I. The strongest motion in tonal music.
vi
Submediant
Deceptive resolution target. Relative minor of the Tonic.
vii°
Leading Tone
Strong tension. Wants to resolve up a half step to I.