Two families of chords, each with its own section: identify them and build them on the staff, with worksheets you can print.
Triads
The basic chord: three notes stacked in thirds. Major, minor, diminished and augmented, in root position and both inversions.
Go to triadsSeventh Chords
A triad with a fourth note added. Dominant, half-diminished and diminished sevenths, in root position and all three inversions.
Go to seventh chords