# C♯ Major 7th piano chord (C♯maj7)

C♯maj7 contains C♯, E♯, G♯ and B♯. A major triad with the major seventh added on top. C♯ and G♯ are black keys; E♯ and B♯ are white.

- Canonical page: https://piano.org/chords/major-7th/c-sharp/
- Entity: chord:major-7th:c-sharp
- Notes: C♯ E♯ G♯ B♯
- Formula: 1 3 5 7
- Intervals from root: P1, M3, P5, M7
- Interval stack (semitones): 4 3 4
- Also written: C♯maj7, C#maj7, C♯ major 7th
- Parameters: A440, 12-TET, 165 mm octave, spans centre to centre

## Construction

| Degree | Note | Interval from root | Semitones |
| --- | --- | --- | --- |
| 1 | C♯ | Perfect unison | 0 |
| 3 | E♯ | Major third | 4 |
| 5 | G♯ | Perfect fifth | 7 |
| 7 | B♯ | Major seventh | 11 |

## Fingering

Rest your right hand over the notes with finger 2 on C♯, finger 3 on E♯, finger 4 on G♯, finger 5 on B♯. The left hand mirrors it.
Right hand 2-3-4-5, left hand 5-4-3-2. Source: piano.org fingering method v1.

## Inversions

| Position | Bass | Notes in order | Figured bass | Span |
| --- | --- | --- | --- | --- |
| Root position | C♯ | C♯3 E♯3 G♯3 B♯4 | 7 | 11 st, 151 mm |
| First inversion (C♯maj7/E♯) | E♯ | E♯3 G♯3 B♯4 C♯4 | 6/5 | 8 st, 110 mm |
| Second inversion (C♯maj7/G♯) | G♯ | G♯3 B♯4 C♯4 E♯4 | 4/3 | 9 st, 124 mm |
| Third inversion (C♯maj7/B♯) | B♯ | B♯4 C♯4 E♯4 G♯4 | 4/2 | 8 st, 110 mm |

## Voicings (10)

| Voicing | Notes | Span | Relation | Omits or adds |
| --- | --- | --- | --- | --- |
| Close, root position | C♯3 E♯3 G♯3 B♯4 | 11 st, 151 mm | identical | none |
| Close, first inversion | E♯3 G♯3 B♯4 C♯4 | 8 st, 110 mm | identical | none |
| Close, second inversion | G♯3 B♯4 C♯4 E♯4 | 9 st, 124 mm | identical | none |
| Close, third inversion | B♯4 C♯4 E♯4 G♯4 | 8 st, 110 mm | identical | none |
| Drop 2 | G♯2 C♯3 E♯3 B♯4 | 16 st, 220 mm | identical | none |
| Drop 3 | E♯2 C♯3 G♯3 B♯4 | 19 st, 261 mm | identical | none |
| Drop 2 and 4 | C♯2 G♯2 E♯3 B♯4 | 23 st, 316 mm | identical | none |
| Shell, root 7 3 | C♯2 B♯3 E♯3 | 16 st, 220 mm | subset | omits G♯ |
| Guide tones, 3 and 7 | E♯3 B♯4 | 7 st, 96 mm | subset | omits C♯ and G♯ |
| Rootless close | E♯3 G♯3 B♯4 | 7 st, 96 mm | subset | omits C♯ |

## Diatonic function by key

| Key | Roman numeral | Function |
| --- | --- | --- |
| D♭ major | Imaj7 | Tonic, home |
| F minor | ♭VImaj7 | Pre-dominant colour |
| A♭ major | IVmaj7 | Subdominant, away from home |
| B♭ minor | ♭IIImaj7 | Relative-major colour |

Classification system: common-practice functional harmony.

## Progressions (9)

| Progression | Key | Role | Sequence | Voice leading |
| --- | --- | --- | --- | --- |
| ii, V, I | D♭ major | Imaj7 | E♭m7 to A♭7 to D♭maj7 | 2 tones held from A♭7 |
| IV, I | D♭ major | Imaj7 | G♭maj7 to D♭maj7 | 2 tones held from G♭maj7 |
| I, vi, ii, V | D♭ major | Imaj7 | D♭maj7 to B♭m7 to E♭m7 to A♭7 | C♯maj7 opens the phrase |
| ♭VI, iv, i, v | F minor | ♭VImaj7 | D♭maj7 to B♭m7 to Fm7 to Cm7 | C♯maj7 opens the phrase |
| i, ♭VI | F minor | ♭VImaj7 | Fm7 to D♭maj7 | 3 tones held from Fm7 |
| IV, V, I | A♭ major | IVmaj7 | D♭maj7 to E♭7 to A♭maj7 | C♯maj7 opens the phrase |
| I, IV | A♭ major | IVmaj7 | A♭maj7 to D♭maj7 | 2 tones held from A♭maj7 |
| ♭III, ♭VI, ii, v | B♭ minor | ♭IIImaj7 | D♭maj7 to G♭maj7 to Cm7♭5 to Fm7 | C♯maj7 opens the phrase |
| i, ♭III | B♭ minor | ♭IIImaj7 | B♭m7 to D♭maj7 | 3 tones held from B♭m7 |

## One-edit neighbors

| Becomes | Edit | Changes | Common tones |
| --- | --- | --- | --- |
| C♯maj9 | 1 3 5 7 9 | adds D♯ | 4 |
| C♯ | 1 3 5 | drops B♯ | 3 |
| C♯7 | 1 3 5 ♭7 | B♯ becomes B | 3 |
| C♯mMaj7 | 1 ♭3 5 7 | E♯ becomes E | 3 |
| C♯6 | 1 3 5 6 | B♯ becomes A♯ | 3 |
| C♯add9 | 1 3 5 9 | B♯ becomes D♯ | 3 |
| C♯9 | 1 3 5 ♭7 9 | B♯ becomes B, D♯ | 3 |
| C♯m | 1 ♭3 5 | E♯, B♯ becomes E | 2 |
| C♯aug | 1 3 ♯5 | G♯, B♯ becomes G× | 2 |
| C♯sus2 | 1 2 5 | E♯, B♯ becomes D♯ | 2 |
| C♯sus4 | 1 4 5 | E♯, B♯ becomes F♯ | 2 |
| C♯m7 | 1 ♭3 5 ♭7 | E♯, B♯ becomes E, B | 2 |

## Set theory

- Absolute pitch classes: {1, 5, 8, 0}
- Relative pitch classes: [0, 4, 7, 11]
- Normal order: [0, 1, 5, 8]
- Prime form: (0158)
- Forte number: 4-20
- Interval vector: <101220>

## Frequencies (close root position)

| Note | MIDI | Frequency |
| --- | --- | --- |
| C♯3 | 49 | 138.59 Hz |
| E♯3 | 53 | 174.61 Hz |
| G♯3 | 56 | 207.65 Hz |
| B♯4 | 60 | 261.63 Hz |

## Questions and answers

### What notes are in C♯maj7?

C♯maj7 contains C♯, E♯, G♯ and B♯. The formula is 1, 3, 5, 7.

### How do you play C♯maj7 on piano?

Play C♯, E♯, G♯ and B♯ together. Right hand fingers 2, 3, 4, 5; left hand 5, 4, 3, 2. C♯ and G♯ are black keys; E♯ and B♯ are white.

### What are the inversions of C♯maj7?

4 positions: root position C♯ E♯ G♯ B♯, C♯maj7/E♯, C♯maj7/G♯, C♯maj7/B♯.

### What keys contain C♯maj7?

4: Imaj7 in D♭ major, ♭VImaj7 in F minor, IVmaj7 in A♭ major, ♭IIImaj7 in B♭ minor.

### What is the difference between C♯maj7 and C♯maj9?

Adds D♯. 4 of the notes are shared.

### What is an easy C♯maj7 for small hands?

The guide tones, 3 and 7 voicing, E♯3 B♯4, spans 7 semitones or about 96 mm.

### What are the frequencies of C♯maj7?

From C♯3 at A440 in 12-TET: 138.59, 174.61, 207.65, 261.63 Hz.

### What is the set class of C♯maj7?

Prime form (0158), Forte 4-20, interval vector &lt;101220&gt;.

### How do I transpose C♯maj7 to another key?

Keep the 1, 3, 5, 7 formula on the new root. Cmaj7 is C, E, G, B; D♭maj7 is D♭, F, A♭, C.

### Is D♭maj7 the same as C♯maj7?

Enharmonically yes: the same piano keys and the same sound, spelled differently.

## Provenance

Every derived value above is computed by the piano.org theory kernel from the root, the quality and the stated parameters. Nothing is hand-entered per chord.

Machine record: https://piano.org/api/knowledge/v1/entities/chord:major-7th:c-sharp
Last reviewed: 2026-08-12