C Minor
m
0 - 3 - 7Root + minor 3rd + perfect 5th
About C Minor
C minor is a barre chord that beginners meet late and then meet constantly. Its notes — C, E♭, G — contain a flat the guitar does not give open, so like G minor it has no first-position shortcut. What it does have is a reputation: this is the chord film music reaches for when something is about to go wrong.
The notes
C, E♭, G — root, minor third, perfect fifth. The E♭ is a semitone below the E natural that sits open on two of the six strings, which is why every C minor voicing has to work around the instrument rather than with it.
The chord is the parallel minor of C major — same root, different third — and swapping between them is the clearest demonstration of what a single semitone does to mood. Songs that darken a chorus by moving from C to Cm are using exactly this.
Where to play it
Third fret, A-string root, A minor shape barred: the usual position, with the root note low and the chord compact. Eighth fret with the low E root gives the same chord an octave deeper and is what players use when the song needs weight.
A partial version on the top four strings — first fret barre with the root on the D string at the tenth — appears in arrangements that need C minor without covering the bass line.
Where it shows up
C minor is the vi of E♭ major and the ii of B♭ — the two keys most horn sections live in. It is also the relative minor of E♭, sharing three flats with it.
In guitar-written music it usually arrives through the parallel switch from C major rather than through its own key, because playing in C minor means three flats and a hand full of barres.