C major seventh chord on piano

The notes and their roles

C major seventh contains C, E, G and B. From the root, the semitone offsets are 0, 4, 7, 11. The degree formula 1, 3, 5, 7 describes each member relative to the root, not its order in a particular voicing.

Read this shape accurately

First inspect the major-triad foundation of this seventh chord. C, E and G are all white keys, but their spacing is not even: C to E is four semitones and E to G is three. Count the black keys between the notes when checking the distances.

Hear the seventh

The seventh here is B. Keeping C · E · G fixed and changing only that note to B♭ produces C dominant seventh. Compare both at the same octave and volume so the one-note difference stays easy to hear.

A dominant-seventh chord is a chord quality. Calling it dominant does not, by itself, establish the key or prove that this chord is functioning as V in a progression.

Choose a bass note

The root-position octave example is C4 · E4 · G4 · B4. Inversions put a different member in the bass while retaining C as the root. The table gives pitch-class order; move the leading notes up an octave as needed to keep each example ascending.

A short listening check

Play C major seventh together, then as separate notes. Name the major third before looking at the display. Repeat in first inversion and check that E is the bass while C remains the root.

1. Choose the displayed root and quality in the chord explorer.
2. Compare root position with one inversion at the same tempo.
3. Save both examples in a named practice collection, or export a reference with note names.