Western theory library
Start with the six-note blues scale and a standard 12-bar form. Real blues practice is broader than this template, especially in phrasing, blue-note intonation, harmony, and form.
I, IV, and V are shown as dominant-seventh chords.
C blues scale
Formula: 1 - b3 - 4 - b5 - 5 - b7
Bar 1 · I
C7
Bar 2 · I
C7
Bar 3 · I
C7
Bar 4 · I
C7
Bar 5 · IV
F7
Bar 6 · IV
F7
Bar 7 · I
C7
Bar 8 · I
C7
Bar 9 · V
G7
Bar 10 · IV
F7
Bar 11 · I
C7
Bar 12 · V
G7
The form explanation follows Open University and Open Music Theory introductions to the 12-bar blues. The tool keeps the common I-IV-V dominant-seventh model visible but does not present it as the only blues form.