Pentatonic & Blues Scales
Pentatonic scales use only 5 notes, making them the simplest and most universally used scales in music. The blues scale adds one extra "blue note" — the tritone — to the minor pentatonic, giving it the grit and tension of the blues.
Major Pentatonic
The major pentatonic removes the 4th and 7th degrees from the major scale: [0, 2, 4, 7, 9]. By dropping the two notes that form half steps, every remaining note sounds good against every other note. It is nearly impossible to play a "wrong" note. Songs like "My Girl" (The Temptations) and "Amazing Grace" are built entirely on the major pentatonic.
Minor Pentatonic
The minor pentatonic removes the 2nd and 6th degrees from the natural minor scale: [0, 3, 5, 7, 10]. It is the backbone of blues, rock, and most guitar soloing. "Smoke on the Water," "Back in Black," and virtually every blues solo are rooted in the minor pentatonic.
The major and minor pentatonics have a relative relationship: C major pentatonic (C D E G A) contains the exact same notes as A minor pentatonic (A C D E G), just starting from a different root.
The Blues Scale
The blues scale is the minor pentatonic with one extra note: the blue note (a tritone, 6 semitones from the root). Formula: [0, 3, 5, 6, 7, 10]. This single addition creates a chromatic run between the 4th and 5th degrees that captures the tension, grit, and emotional depth of the blues. Musicians typically bend into or slide through the blue note rather than lingering on it.
The blues scale works even over major-key progressions, creating a deliberate clash between the minor 3rd in the melody and the major 3rd in the chords — a sound so characteristic of blues and rock that it defines American popular music.
In ChordColor
All three scales are available in the scale picker. When the blues scale is selected, the blue note appears in its characteristic teal color (tritone), visually distinct from the surrounding lime-green (perfect 4th) and blue (perfect 5th).