C dominant seventh piano chord

How to play C7 on piano

First, find C, the root of this chord. Then add E, the major third. Add G to complete the triad. The fourth note, B♭, creates the dominant seventh.

Play the notes together to hear the harmony, or one at a time to hear how the intervals form the chord. Start at a comfortable octave; the diagram shows one reference voicing, not the only valid place to play it.

What makes C7 distinctive?

C7 is a dominant seventh chord, not a major seventh. It is built from the C major triad plus B♭, a minor seventh above C.

Compare this chord with another

Compare C7 with C major (C–E–G). Add and remove B♭ without moving the other three notes to hear the new tension.

A practice exercise for C7

Play C–E–G, then add B♭ slowly. Listen for the stronger desire to move onward to another chord.

One mistake to avoid

C7 uses B♭, while Cmaj7 uses B natural. Do not use those names interchangeably.

A simple practice routine

• Say each note name aloud as you find its key.
• Play the root-position chord, then release the keys evenly.
• Move to first inversion and listen to the bass change.
• Return to root position without looking at the diagram.

Finger numbers depend on your hand size, octave and musical context; there isn't one universally correct fingering for every voicing.