Chord reference · four-note chord
C#7 chord (C-sharp dominant seventh)
The C#7 chord contains 4 written tones: C♯, E♯, G♯, B. Its interval formula is 1–3–5–♭7.
C#7 chord notes and interval formula
The formula 1–3–5–♭7 means the chord is measured from C♯ using the root, major third, perfect fifth, and minor seventh. In semitone numbers from the root, the pattern is 0–4–7–10.
| Degree | Interval | Semitones | Note |
|---|---|---|---|
| 1 | Root | 0 | C♯ |
| 3 | Major Third | 4 | E♯ |
| 5 | Perfect Fifth | 7 | G♯ |
| ♭7 | Minor Seventh | 10 | B |
How to play C#7 on piano
Start with the notes in root position from low to high: C♯ – E♯ – G♯ – B. Right hand 1–2–3–5; left hand 5–3–2–1 is a useful starting point, but black-key combinations and melodic movement may make another fingering more comfortable.
For a cleaner accompaniment, place the root in the left hand and play the remaining tones in the right. With extended chords, keep the third and seventh because they identify the chord quality most clearly.
How to play C#7 on guitar
Try the shape x-4-3-4-0-4 in standard tuning, read from low E to high E. The sounding-string details are: E mute; A fret 4: C♯; D fret 3: E♯; G fret 4: B; B open: B; E fret 4: G♯. Keep every note clear and release pressure from strings marked “x.”
This is one voicing, not the only correct shape. The chord remains C#7 whenever the essential pitch classes are present; doubling, omission, and bass-note choice change the voicing rather than the basic chord name.
C#7 inversions and slash chords
Inversions keep the same notes but place a different chord tone in the bass. They are useful for smoother bass lines, compact keyboard movement, and alternative guitar voicings.
| Position | Symbol | Notes low to high | Bass |
|---|---|---|---|
| Root position | C#7 | C♯ – E♯ – G♯ – B | C♯ |
| 1st inversion | C#7/E# | E♯ – G♯ – B – C♯ | E♯ |
| 2nd inversion | C#7/G# | G♯ – B – C♯ – E♯ | G♯ |
| 3rd inversion | C#7/B | B – C♯ – E♯ – G♯ | B |
What C#7 sounds like and where it fits
The C-sharp dominant seventh chord is strongly directional. Dominant seventh chords contain a tritone between the third and flat seventh. That interval drives the chord toward a tonic whose root is a perfect fourth above the chord root. For example, C#7 has a natural pull toward a tonic on F♯.
C#7 compared with similar chords
Small interval changes create different chord names. Use this table to avoid confusing C#7 with nearby structures.
| Chord | Quality | Formula | Notes |
|---|---|---|---|
| C#maj7 | Major Seventh | 1–3–5–7 | C♯, E♯, G♯, B♯ |
| C#m7 | Minor Seventh | 1–♭3–5–♭7 | C♯, E, G♯, B |
| C#9 | Dominant Ninth | 1–3–5–♭7–9 | C♯, E♯, G♯, B, D♯ |
Frequently asked questions
What notes are in the C#7 chord?
The C#7 chord contains C♯, E♯, G♯, B. Its interval formula is 1–3–5–♭7.
How do you play C#7 on piano?
Play C♯, E♯, G♯, B together. A practical root-position fingering is right hand 1–2–3–5; left hand 5–3–2–1; adjust the fingering to your hand and musical context.
How do you play C#7 on guitar?
One compact standard-tuning shape is x-4-3-4-0-4 from the low E string to the high E string. An “x” means mute that string.
What does the symbol C#7 mean?
The root is C♯. The suffix 7 identifies a dominant seventh structure with the formula 1–3–5–♭7.
How many inversions does C#7 have?
A 4-note chord has 4 closed-position arrangements when every chord tone is retained: root position plus 3 inversions. Extended practical voicings may omit notes.