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.
Major Chords
The bright, happy chord. A major 3rd with a minor 3rd stacked on top.
Minor Chords
The darker, sadder chord. The same two thirds as major, flipped.
Diminished Chords
Tense and unstable. Two minor 3rds — the 5th shrinks to a tritone.
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.
Related Tools
Chord Finder
Identify any chord by clicking keys — inversions and voicing boxes.
Chord Drill
Timed chord practice with MIDI grading and mastery progression.
Scale Drill
Drill scales with MIDI input, fingering guidance, and a tempo ladder.
Circle of Fifths
Interactive key relationships — scales, chords, and staff notation.
Practice Room
The central MIDI practice hub — drills, free play, and live feedback.
Key Signature Quiz
Name the sharps and flats of every major and minor key.
Interval Trainer
Learn to identify intervals by sight and sound.
Note Reading
Practice reading notes on the grand staff.
Rhythm Drill
Tap-input rhythm training from quarter notes to syncopation.
MIDI Monitor
See every note, velocity, and pedal event from your keyboard live.
Skill Diagnostic
Benchmark your playing and get a personalized skill map.
MIDI Latency Calibration
Measure and correct your controller’s latency for fair timing scores.
Play Along
Play along with guided sequences on a live keyboard display.