4 notes · 1 · 3 · 5 · ♭7

C Dominant Seventh Piano Chord (C7)

C7 is built from C, E, G and Bb — the formula 1 · 3 · 5 · ♭7, or 4, 7 and 10 semitones above C. The shape uses 3 white and 1 black key, and you can hear it, invert it and compare it below.

Root noteChord type

Chord

C Dominant seventh

Notes

C · E · G · A#

Formula

1 · 3 · 5 · ♭7

Right hand

1 · 2 · 3 · 5

Choose a chord, then play it. Finger numbers run from thumb (1) to little finger (5).

The finder above already holds C7. Press P or the Play chord button to hear C, E, G, Bb sounded together, then change the root or the chord type to compare it with something else.

Chord tones

The notes in C7

A dominant seventh chord is a major triad with a minor seventh added on top. The tritone between its third and its seventh is unstable and pulls strongly towards the chord a fifth below, which is what makes it the engine of blues, gospel and most cadences. In a major key it is built on the fifth degree.

Each tone of C dominant seventh with its interval, scale degree, distance in semitones from C and a suggested right-hand finger.
Note	Interval	Degree	Semitones	Right hand
Cwhite key	Root	1	0	1 · thumb
Ewhite key	Major third	3	4	2 · index finger
Gwhite key	Perfect fifth	5	7	3 · middle finger
Bbblack key	Minor seventh	♭7	10	5 · little finger

Step by step

How to play C7 on piano

Find C: it is the white key immediately left of every group of two black keys.
Build upwards from C using 4, 7 and 10 semitones to reach E, G and Bb.
With the right hand, place finger 1 on C, finger 2 on E, finger 3 on G and finger 5 on Bb. Keep the wrist level and the knuckles rounded.
Move your hand a little further in towards the fallboard so the black key sits comfortably under your fingers.
Play the notes together, then one at a time from the bottom up, and listen to how C7 settles.
Try first inversion as well: E – G – Bb – C. Inversions let you change chords without jumping around the keyboard.

Inversions

C7 in 4 positions

An inversion keeps the same 4 notes and simply moves the lowest one up an octave. Learning them means you can change chords with small hand movements instead of jumping to a new part of the keyboard.

Root position

C – E – G – Bb

The root C is the lowest note. This is the shape most people learn first.

First inversion

E – G – Bb – C

E is the lowest note, so the major third sits in the bass and the notes below it move up an octave.

Second inversion

G – Bb – C – E

G is the lowest note, so the perfect fifth sits in the bass and the notes below it move up an octave.

Third inversion

Bb – C – E – G

Bb is the lowest note, so the minor seventh sits in the bass and the notes below it move up an octave.

In context

Which keys contain C7

In F major the chord functions as V7. Altogether it is produced by the scales of 3 keys, so learning it once pays off in several places.

F majorV7
D minorVII7
F harmonic minorV7

Chord tones are spelled by the degree they occupy, so the third of a minor chord is written as a flat rather than a sharp even though it is the same key on the piano. A double sharp such as F## means the key one whole tone above F.

Compare

C7 against Cmaj7

C7 and Cmaj7 share C, E and G. Moving the major seventh B down 1 semitone to the minor seventh Bb turns Cmaj7 into C7.

Practise the pair together: hold the shared notes C, E, G still and move only the one finger. Hearing that single change is the quickest way to recognise the two chords by ear.

Open Cmaj7 →

Good questions

C7 questions

What notes are in the C7 chord?

C7 contains C, E, G and Bb. Counted from the root, that is the formula 1 · 3 · 5 · ♭7, or 4, 7 and 10 semitones above C.

What is the right-hand fingering for C7?

A comfortable beginner fingering is 1 (thumb) on C, 2 (index finger) on E, 3 (middle finger) on G and 5 (little finger) on Bb. Finger numbers run from the thumb (1) to the little finger (5), and they change once you start using inversions.

How is C7 different from Cmaj7?

C7 and Cmaj7 share C, E and G. Moving the major seventh B down 1 semitone to the minor seventh Bb turns Cmaj7 into C7.

Which keys use the C7 chord?

It occurs naturally in F major (V7), D minor (VII7) and F harmonic minor (V7). The roman numeral shows which degree of the key the chord is built on.

What are the inversions of C7?

root position is C – E – G – Bb, first inversion is E – G – Bb – C, second inversion is G – Bb – C – E and third inversion is Bb – C – E – G. Every inversion holds the same notes; only the lowest one changes.