C♯ Suspended 4th Chord (C#sus4, Dbsus4) on Piano
The C#sus4 chord (C# suspended 4th) is built from 3 notes: C# – F# – G#. It is also written as Dbsus4.
Play these notes on a MIDI keyboard, your computer keyboard, or the on-screen keys and ChordKeys will name the chord back to you.
Notes and intervals
| Note | Degree | Interval from C# | Semitones |
|---|---|---|---|
| C# | 1 | root | 0 |
| F# | 4 | perfect 4th | 5 |
| G# | 5 | perfect 5th | 7 |
Inversions
Rearranging which note sits at the bottom gives you 3 playable voicings of the same chord. Inversions let you move between chords with less hand movement.
| Voicing | Notes | Bass note |
|---|---|---|
| Root position | C# – F# – G# | C# in the bass |
| 1st inversion | F# – G# – C# | F# in the bass |
| 2nd inversion | G# – C# – F# | G# in the bass |
How the suspended 4th chord is built
Every suspended 4th chord uses the same interval formula: 1 (0 semitones), 4 (5 semitones), 5 (7 semitones). Starting on C# and applying that formula produces C#, F#, G#. Learn the formula once and you can build a suspended 4th chord on any of the twelve roots.
Keys that contain C#sus4
Every note of C#sus4 belongs to these keys, so it will sit naturally in a progression written in any of them.
Other chords on C#
Suspended 4th chords on other roots
Frequently asked questions
What notes are in a C#sus4 chord?
A C#sus4 chord contains the notes C#, F#, G#. Those are the 1, 4, 5 degrees measured from the root note C#.
How do you play C#sus4 on piano?
Place your thumb on C#, then add F# and G# above it. With a right hand in root position the common fingering is 1–3–5.
Is C#sus4 the same as Dbsus4?
Yes. C#sus4 and Dbsus4 are enharmonic equivalents — they sound identical and use the same piano keys. Which spelling you use depends on the key you are playing in.