Root position
C# – F# – G#The root C# is the lowest note. This is the shape most people learn first.
3 notes · 1 · 4 · 5
C# Suspended Fourth Piano Chord (C#sus4)
C#sus4 is built from C#, F# and G# — the formula 1 · 4 · 5, or 5 and 7 semitones above C#. The shape uses 0 white and 3 black keys, and you can hear it, invert it and compare it below.
Chord
C# Suspended fourth
Notes
C# · F# · G#Formula
1 · 4 · 5Right hand
1 · 4 · 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#sus4. Press P or the Play chord button to hear C#, F#, G# sounded together, then change the root or the chord type to compare it with something else.
Chord tones
The notes in C#sus4
A suspended fourth chord replaces the third with the fourth degree. The fourth sits one semitone above the major third and leans onto it, so a sus4 is usually heard as a delay that resolves into the plain triad underneath it.
| Note | Interval | Degree | Semitones | Right hand |
|---|---|---|---|---|
| C#black key | Root | 1 | 0 | 1 · thumb |
| F#black key | Perfect fourth | 4 | 5 | 4 · ring finger |
| G#black key | Perfect fifth | 5 | 7 | 5 · little finger |
Step by step
How to play C#sus4 on piano
- Find C#: it is the first black key in a group of two.
- Build upwards from C# using 5 and 7 semitones to reach F# and G#.
- With the right hand, place finger 1 on C#, finger 4 on F# and finger 5 on G#. 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#sus4 settles.
- Try first inversion as well: F# – G# – C#. Inversions let you change chords without jumping around the keyboard.
Inversions
C#sus4 in 3 positions
An inversion keeps the same 3 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
F# – G# – C#F# is the lowest note, so the perfect fourth sits in the bass and the notes below it move up an octave.
Second inversion
G# – C# – F#G# is the lowest note, so the perfect fifth sits in the bass and the notes below it move up an octave.
In context
Which keys contain C#sus4
In D♭ major the chord functions as Isus4. Altogether it is produced by the scales of 10 keys, so learning it once pays off in several places.
- D♭ majorIsus4
- E majorvisus4
- F♯ majorVsus4
- A majoriiisus4
- B majoriisus4
- C♯ minorisus4
- E♭ minorVIIsus4
- F♯ minorvsus4
- G♯ minorivsus4
- B♭ minorIIIsus4
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#sus4 against C# major
C#sus4 and C# major share C# and G#. Moving the major third E# up 1 semitone to the perfect fourth F# turns C# major into C#sus4.
Practise the pair together: hold the shared notes C#, 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# major →Good questions
C#sus4 questions
What notes are in the C#sus4 chord?
C#sus4 contains C#, F# and G#. Counted from the root, that is the formula 1 · 4 · 5, or 5 and 7 semitones above C#.
What is the right-hand fingering for C#sus4?
A comfortable beginner fingering is 1 (thumb) on C#, 4 (ring finger) on F# and 5 (little finger) on G#. Finger numbers run from the thumb (1) to the little finger (5), and they change once you start using inversions.
How is C#sus4 different from C# major?
C#sus4 and C# major share C# and G#. Moving the major third E# up 1 semitone to the perfect fourth F# turns C# major into C#sus4.
Which keys use the C#sus4 chord?
It occurs naturally in D♭ major (Isus4), E major (visus4), F♯ major (Vsus4), A major (iiisus4), B major (iisus4) and C♯ minor (isus4) among others. The roman numeral shows which degree of the key the chord is built on.
What are the inversions of C#sus4?
root position is C# – F# – G#, first inversion is F# – G# – C# and second inversion is G# – C# – F#. Every inversion holds the same notes; only the lowest one changes.
Is C#sus4 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.