Root position
C# – E# – G# – BThe root C# is the lowest note. This is the shape most people learn first.
4 notes · 1 · 3 · 5 · ♭7
C# Dominant Seventh Piano Chord (C#7)
C#7 is built from C#, E#, G# and B — the formula 1 · 3 · 5 · ♭7, or 4, 7 and 10 semitones above C#. The shape uses 2 white and 2 black keys, and you can hear it, invert it and compare it below.
Chord
C# Dominant seventh
Notes
C# · F · G# · BFormula
1 · 3 · 5 · ♭7Right hand
1 · 2 · 3 · 5C
D
E
F
G
A
B
C
C#
D#
F#
G#
A#
Choose a chord, then play it. Finger numbers run from thumb (1) to little finger (5).
The finder above already holds C#7. Press P or the Play chord button to hear C#, E#, G#, B sounded together, then change the root or the chord type to compare it with something else.
Chord tones
The notes in C#7
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.
| Note | Interval | Degree | Semitones | Right hand |
|---|---|---|---|---|
| C#black key | Root | 1 | 0 | 1 · thumb |
| E#white key | Major third | 3 | 4 | 2 · index finger |
| G#black key | Perfect fifth | 5 | 7 | 3 · middle finger |
| Bwhite key | Minor seventh | ♭7 | 10 | 5 · little finger |
Step by step
How to play C#7 on piano
- Find C#: it is the first black key in a group of two.
- Build upwards from C# using 4, 7 and 10 semitones to reach E#, G# and B.
- With the right hand, place finger 1 on C#, finger 2 on E#, finger 3 on G# and finger 5 on B. Keep the wrist level and the knuckles rounded.
- Move your hand a little further in towards the fallboard so the black keys sit comfortably under your fingers.
- Play the notes together, then one at a time from the bottom up, and listen to how C#7 settles.
- Try first inversion as well: E# – G# – B – C#. Inversions let you change chords without jumping around the keyboard.
Inversions
C#7 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.
First inversion
E# – G# – B – 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# – B – 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
B – C# – E# – G#B 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 C#7
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
- E♭ 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
C#7 against C#maj7
C#7 and C#maj7 share C#, E# and G#. Moving the major seventh B# down 1 semitone to the minor seventh B turns C#maj7 into C#7.
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 C#maj7 →Good questions
C#7 questions
What notes are in the C#7 chord?
C#7 contains C#, E#, G# and B. 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 C#7?
A comfortable beginner fingering is 1 (thumb) on C#, 2 (index finger) on E#, 3 (middle finger) on G# and 5 (little finger) on B. Finger numbers run from the thumb (1) to the little finger (5), and they change once you start using inversions.
How is C#7 different from C#maj7?
C#7 and C#maj7 share C#, E# and G#. Moving the major seventh B# down 1 semitone to the minor seventh B turns C#maj7 into C#7.
Which keys use the C#7 chord?
It occurs naturally in F♯ major (V7), E♭ 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 C#7?
root position is C# – E# – G# – B, first inversion is E# – G# – B – C#, second inversion is G# – B – C# – E# and third inversion is B – C# – E# – G#. Every inversion holds the same notes; only the lowest one changes.
Is C#7 the same as the D♭ chord?
On an equal-tempered piano C# and D♭ are the same key, so the chords sound identical. Written music chooses between them according to the key signature: pages here are named after the sharp spelling of the root, and the chord tones are then spelled by the degree each one occupies, which is why a double sharp occasionally appears.