Blues scale: notes, formula and sound

The blues scale is a six-note scale that has the sound of blues, rock and early jazz. It is the minor pentatonic scale with one extra note added, and that extra note is what gives it its gritty, tense character. If you can play the minor pentatonic scale, you are one note away from the blues scale.

The blues scale formula

The scale has six notes: 1 ♭3 4 ♭5 5 ♭7. In steps from the tonic, the pattern is step and a half, whole, half, half, step and a half, whole. The two half steps in a row (from 4 to ♭5 and from ♭5 to 5) are what make the scale sound so tense.

The blue note is also written as a sharp fourth (♯4), depending on the context. In A, it could be D♯ instead of E♭. It is the same pitch on a piano. A flat fifth is the most common way to name it when the scale is written out. It is the interval of a tritone from the root.

Where does the blue note come from?

The blues grew out of African American music in the American South, where singers and instrumentalists bent notes between the pitches of the piano. Written music has to choose a spelling, so the blues scale is the closest fixed version of those bent notes. On a guitar, a player can bend a string up to the blue note. On a piano, the note is played directly or the player slides between a note and its neighbor.

How to build it in any key

1. Write the minor pentatonic scale of the key.
2. Add the flat fifth, which is a half step below the fifth degree.
3. Check that you now have six notes: 1 ♭3 4 ♭5 5 ♭7.

In E, the minor pentatonic is E G A B D. The flat fifth is B♭, which goes between A and B, giving E G A B♭ B D.

How to use the blues scale

The blues scale works well over the dominant seventh chords of a 12-bar blues, and many players use the same scale of the key over all three chords. The tension of the blue note makes it best as a passing note: slide through it, bend into it or land on it briefly, rather than holding it. Held too long, it can feel unresolved.

• Use it for solos in blues, rock and funk.
• Play the minor third and the major third together in the same phrase for the classic bluesy clash.
• Resolve the blue note up to the fifth or down to the fourth.
• Mix in notes from the major pentatonic scale for a brighter, major-blues sound.

Blues scale or minor pentatonic?

Many guitarists play the minor pentatonic scale most of the time, and use the blue note sparingly as an extra color. The scale is the same, with one note of added tension. See the minor pentatonic scale page for the five-note version.

Blues scale in the major key

There is also a major blues scale: 1 2 ♭3 3 5 6. It is the major pentatonic scale with a flat third added as a passing note. It has a brighter, more country-and-gospel feeling. Players often mix the two blues scales over one tune, because the clash between the minor third and the major third is the heart of the blues sound.

When you practice, try bending a string or sliding a finger from the minor third up toward the major third. That small, unstable move is typical of blues playing and of blues singing, and it is a reminder that the scale is a guide, not a fixed set of pitches.

One more thing to try

Play the scale slowly up and down in A, then in E, and then in D, which are the three keys guitarists use most for the blues. Notice that the blue note always sits a half step below the fifth. Then record a simple loop of one chord and improvise over it with the scale, using only three or four notes at a time.

Blues scale in every key

Check yourself

Related pages

• Minor pentatonic scale: formula and uses
• The pentatonic scale: major and minor explained
• 12-bar blues: chord pattern and how to play it
• Tritone: the interval of six half steps
• Minor scales: natural, harmonic and melodic