Build a chord note by note on the keyboard and see it named and spelled as you go.

Chord Builder

Every triad is just two stacked thirds — a simple semitone recipe that works from any root note. Pick a chord quality below and watch it get built one semitone at a time: count along, hear each tone land, then hear the full chord. Switch roots to see that the shape never changes.

4 + 3

Major Chords

The bright, happy chord. A major 3rd with a minor 3rd stacked on top.

3 + 4

Minor Chords

The darker, sadder chord. The same two thirds as major, flipped.

3 + 3

Diminished Chords

Tense and unstable. Two minor 3rds — the 5th shrinks to a tritone.

4 + 4

Augmented Chords

Dreamlike and unresolved. Two major 3rds — the 5th stretches a step wider.

Want the full reference for any specific chord? Browse the chord library, or go deeper on the theory in Triads from the Chord Mastery Series.

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