The key of C Major mostly uses the notes of the C major scale, which are C, D, E, F, G, A, and B. The key signature has no sharps or flats, and its relative minor key is A minor.

The C Major Key Signature

It’s the easiest key for musicians to think in and is a good doorway into the world of music theory.

C Major Diatonic Chords

The C Major key uses the scale degree chords of the G major scale, which are C, Dm, Em, F, G, Am and Bmb5.

I ii iii IV V vi vii°
C Dm Em FG Am Bmb5

C Major Cadences

An easy way to find out if a song is in the C Major key is to look for cadences. A cadence is a melodic or chord progression that moves towards a point of rest or resolution and is the most common way to define a key.

Classical Cadence:

  • Intervals: IV – V – I
  • Chords: F – G – C

Jazz Cadence:

  • Intervals: ii – V – I
  • Chords: Dm – G – C