The key of C# major is built from C#, D#, F, F#, G#, A#, C. Its relative minor is A# minor, and its diatonic chords are C#, D#m, Fm, F#, G#, A#m, Cdim. Below you will find the key signature, the chord table, the relative key and the progressions that belong here.
What notes are in the key of C# major?
The key of C# major uses seven notes: C#, D#, F, F#, G#, A#, C. In the sharp spelling used on this site, 5 of those seven notes are sharps (C#, D#, F#, G#, A#), and the rest are natural notes. The tonic is C#, the note the key is named after and the note melodies in this key return to. Every chord, scale and melody in the key of C# major is built from these seven notes, which is why learning the note list is the first step to playing in the key.
| Degree | Note |
|---|---|
| 1 | C# |
| 2 | D# |
| 3 | F |
| 4 | F# |
| 5 | G# |
| 6 | A# |
| 7 | C |
The scale of the key of C# major is the C# major scale, which uses exactly these notes in order. Practise that scale up and down before you work on the chords, because the scale is the map of the key: once your fingers know the notes, the chords below are simply groups of those notes played together. Use the Key Finder and the Circle of Fifths to see the key of C# major in context, and the Scale Degree Calculator to check which degree any note belongs to.
Chords in the key of C# major
There are seven diatonic chords in the key of C# major, one built on each note of the key. The table below lists them in order, with their degree and their quality, and each chord links to its full page.
| Degree | Chord | Quality |
|---|---|---|
| I | C# | major |
| ii | D#m | minor |
| iii | Fm | minor |
| IV | F# | major |
| V | G# | major |
| vi | A#m | minor |
| vii° | Cdim | Diminished |
The I chord is C#, a major chord built from C#, F, G#. In the key of C# major it is the chord on degree I, and its job depends on that position: the tonic chord is home, the dominant chord pulls home, and the chords in between create the journey. Learn C# on its own page — C# guitar chord — and then practise it in the progressions below, where it appears alongside the other chords of this key.
The ii chord is D#m, a minor chord built from D#, F#, A#. In the key of C# major it is the chord on degree ii, and its job depends on that position: the tonic chord is home, the dominant chord pulls home, and the chords in between create the journey. Learn D#m on its own page — D#m guitar chord — and then practise it in the progressions below, where it appears alongside the other chords of this key.
The iii chord is Fm, a minor chord built from F, G#, C. In the key of C# major it is the chord on degree iii, and its job depends on that position: the tonic chord is home, the dominant chord pulls home, and the chords in between create the journey. Learn Fm on its own page — Fm guitar chord — and then practise it in the progressions below, where it appears alongside the other chords of this key.
The IV chord is F#, a major chord built from F#, A#, C#. In the key of C# major it is the chord on degree IV, and its job depends on that position: the tonic chord is home, the dominant chord pulls home, and the chords in between create the journey. Learn F# on its own page — F# guitar chord — and then practise it in the progressions below, where it appears alongside the other chords of this key.
The V chord is G#, a major chord built from G#, C, D#. In the key of C# major it is the chord on degree V, and its job depends on that position: the tonic chord is home, the dominant chord pulls home, and the chords in between create the journey. Learn G# on its own page — G# guitar chord — and then practise it in the progressions below, where it appears alongside the other chords of this key.
The vi chord is A#m, a minor chord built from A#, C#, F. In the key of C# major it is the chord on degree vi, and its job depends on that position: the tonic chord is home, the dominant chord pulls home, and the chords in between create the journey. Learn A#m on its own page — A#m guitar chord — and then practise it in the progressions below, where it appears alongside the other chords of this key.
The vii° chord is Cdim, a diminished chord built from C, D#, F#. In the key of C# major it is the chord on degree vii°, and its job depends on that position: the tonic chord is home, the dominant chord pulls home, and the chords in between create the journey. Learn Cdim on its own page — Cdim guitar chord — and then practise it in the progressions below, where it appears alongside the other chords of this key.
Relative minor
The relative minor of C# major is the key of A# minor. The two keys share exactly the same notes — C#, D#, F, F#, G#, A#, C — but they have different home chords: in C# major the home chord is C#, while in A# minor the home chord is the chord built on A#. That is the whole difference between relative keys: same notes, different tonic. Because they share notes, a melody or progression in C# major can move into A# minor without changing key signature, which is why relative keys are the most common modulation in popular music. Practise the A# minor scale alongside the C# major scale and notice that the notes are identical — only the starting note, and therefore the feeling of home, has changed. The Relative Major / Minor Finder shows the relative key of any key instantly.
Progressions in this key
The progressions that work in the key of C# major include I–V–vi–IV in C# major, I–vi–IV–V in C# major, ii–V–I in C# major, 12 bar blues progression in C# major. Each one uses only the diatonic chords listed above, so every chord in the progression belongs to the key and no chromatic notes are needed. Start with the first progression in the list and play it slowly, one chord per bar, listening to how each chord leads to the next. Then try the others and notice how the same seven chords can produce very different feelings simply by changing their order. The Chord Progression Builder and the Progression Finder let you build and identify progressions in the key of C# major and in any other key.
Frequently asked questions
Is C# major a good key for beginners?
It is as good as any key once you know its notes (C#, D#, F, F#, G#, A#, C) and its chords (C#, D#m, Fm, F#, G#, A#m, Cdim). The key of C# major is neither easier nor harder in principle than other keys — the difficulty depends on the instrument and the voicings you choose.
What notes are in the key of C# major?
The key of C# major contains C#, D#, F, F#, G#, A#, C. Those seven notes are the whole key: every scale, chord and melody in this key is built from them, and the key signature follows from which of them are sharps.
What are the chords in the key of C# major?
The seven diatonic chords are C#, D#m, Fm, F#, G#, A#m, Cdim. They are built on the seven notes of the key, one chord per note, in the order shown in the table above. Each chord links to its own page from the chord table.
What is the relative minor of C# major?
The relative minor of C# major is A# minor. The two keys share the same notes — C#, D#, F, F#, G#, A#, C — but have different home chords, so a song can move between them without changing key signature.
How many sharps are in the key of C# major?
In the sharp spelling used here, 5 of the seven notes are sharps. The key signature of C# major follows from those notes, and the Circle of Fifths shows where this key sits among all twelve major and minor keys.