Scale degrees · C major

The 13 of C is A

The 13 (thirteen) of C is A: a major thirteenth above the root.

C — the root, 1A — the 13

How to find it

A 13th is a 6th an octave up, so it takes the 6th's letter: C, D, E, F, G, A.

Then the sound: a major thirteenth is 21 semitones above C, which is exactly where A is — no sharp or flat needed.

Where you meet it

The 13 is the 6 an octave up: the top of a thirteenth chord, and of the classic dominant voicing with the 3 and the ♭7.

In C13:

C · E · G · B♭ · D · A

The 13 in every key

KeyThe 13
CA
GE
DB
AF♯
EC♯
BG♯
F♯D♯
D♭B♭
A♭F
E♭C
B♭G
FD

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