C Suspended 4th Chord
Chord Tones: C Suspended 4th Chord
Symbol: sus4, sus — Formula: 1-4-5
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | C4 | 261.626 Hz |
| 4 | F4 | 349.228 Hz |
| 5 | G4 | 391.995 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | Csus4 |
| All Common Symbols | sus4, sus |
| Interval Formula | 1-4-5 |
| Harmonic Category | open |
Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.
Inversions
| Inversion | Notes (low to high) | Bass Note | Slash Notation |
|---|---|---|---|
| Root Position | C4 – F4 – G4 | C | C Suspended 4th Chord |
| First Inversion | F4 – G4 – C4 | F | C Suspended 4th Chord/F |
| Second Inversion | G4 – C4 – F4 | G | C Suspended 4th Chord/G |
Harmonic Function
The C sus4 chord commonly functions as the tonic (I) in C major/minor. Its harmonic role varies by key — in major keys it provides stable harmonic grounding.
The sus4 chord replaces the third with a perfect fourth, creating tension that traditionally resolves down to the major third. It creates anticipation and is common before dominant chords. The C Suspended 4th Chord specifically contains 3 notes: C, F, G (formula: 1-4-5). On piano, C-rooted chords sit entirely on white keys in their basic triad form, making them the first chords most students learn. Pop, folk, and singer-songwriter music heavily use C-rooted chords because open-position guitar voicings and piano shapes are immediately accessible.
Common Progressions
The C Suspended 4th Chord frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
Songs Featuring the Suspended 4th Chord
Well-known songs where the C Suspended 4th Chord — or this chord type — plays a prominent role:
- Scarborough Fair – Simon & Garfunkel
- The Seeker – The Who
- Born on the Bayou – CCR
Tuning Frequencies Across Temperaments
Frequencies shown at A=440 Hz. View full temperament data for any note.
| Note | Equal Temp. | Pythagorean | Just Intonation |
|---|---|---|---|
| C4 | 261.626 Hz | 260.740 Hz | 261.626 Hz |
| F4 | 349.228 Hz | 347.654 Hz | 348.834 Hz |
| G4 | 391.995 Hz | 391.111 Hz | 392.438 Hz |
Scales Containing the C Suspended 4th Chord
These scales include the C Suspended 4th Chord as a diatonic or characteristic chord: