semicord

C13 C dominant thirteenth chord

Notes
C E G Bb D F A
Formula
1 3 5 b7 9 11 13
Semitones
0 4 7 10 14 17 21 above the root
Other symbols
Cdom13

C to E is a major third (4 semitones), E to G is a minor third (3 semitones), G to Bb is a minor third (3 semitones), Bb to D is a major third (4 semitones), D to F is a minor third (3 semitones), F to A is a major third (4 semitones). A dominant seventh with the thirteenth, A, on top. The full chord has seven notes and a guitar has six strings, so players keep the root, the third E, the seventh Bb and the thirteenth A, and leave out the fifth, the ninth and above all the eleventh F, which clashes with the third. The thirteenth is the sixth an octave up; it is a 13 and not a 6 chord because the seventh is there.

C13 on the piano

C4D4E4F4G4A4B4C5D5E5F5G5A5B5C#4Eb4F#4Ab4Bb4C#5Eb5F#5Ab5Bb5CC4EGBbC5DFA

Root position from C4: C4, E4, G4, Bb4, D5, F5, A5. Middle C is C4.

C13 on the guitar

Standard tuning (E A D G B E). Strings run low E on the left to high e on the right, frets downwards; × is a muted string, ○ an open string, and each dot shows the note it sounds, with the root in blue-green. Every shape below has C as its lowest note.

×CC×BbBbEEAA
A-shape, root on the A string at fret 3
x 3 x 3 5 5 (low E to high e)
Sounds C3 Bb3 E4 A4, fifth, ninth and eleventh left out
8frCC×BbBbEEAA×
E-shape, root on the E string at fret 8
8 x 8 9 10 x (low E to high e)
Sounds C3 Bb3 E4 A4, fifth, ninth and eleventh left out

The E-shape and A-shape grips are movable: an E-shape chord's root is the note under your first finger on the low E string, an A-shape chord's root is the note on the A string. Slide the same grip up or down to play dominant thirteenth chords on other roots.

Inversions of C13

An inversion puts a note other than the root in the bass. The name is what semicord's chord finder calls those notes played bottom to top; a slash name like C/E means a C chord with E in the bass.

PositionNotes, bass firstNamedListen
Root positionC E G Bb D F AC13
1st inversionE G Bb D F A CC13/E
2nd inversionG Bb D F A C EGm13 (also read as C13/G)
3rd inversionBb D F A C E GC13/Bb
4th inversionD F A C E G BbC13/D
5th inversionF A C E G Bb DC13/F
6th inversionA C E G Bb D FC13/A

Where C13 fits

C13 is V13 in F major. Played with its third, seventh and thirteenth (E, Bb, A) over the root, it is the standard dominant chord of jazz and soul, resolving to F.