How to Construct Pentatonic and Blues Scales

What is a Pentatonic Scale?

A pentatonic scale is a five-note scale. There are two pentatonic scales that are used frequently in guitar playing: the major pentatonic and the minor pentatonic. These scales are used in many different styles, including blues, rock, jazz, country, and heavy metal. Almost every guitarist has used this scale in their music in some way.

The Major Pentatonic Scale

The major pentatonic scale can be viewed as a major scale with two notes left out. The first, second, third, fifth, and sixth degrees of the major scale make up the major pentatonic scale. The fourth and seventh degrees are omitted. For example, the C major pentatonic scale would be: C, D, E, G, A. F and B are left out because they are the fourth and seventh degrees of the C major scale.

The formula for the major pentatonic scale can be written as 1, 2, 3, 5, 6. These numbers are the scale degrees of the major pentatonic scale in relation to the degrees of the major scale.

The Minor Pentatonic Scale

The minor pentatonic scale can be derived from the major or natural minor scale. It is useful to know both formulas so you can more easily see the relationships between the minor pentatonic and other scales. These formulas are shown below:

deriving from the major scale: 1, b3, 4, 5, b7
deriving from the minor scale: 1, 3, 4, 5, 7

A C minor pentatonic scale is shown below:

The Blues Scale

The blues scale is a six-note scale based on the minor pentatonic. A b5 is added to the minor pentatonic scale to produce the blues scale. A C blues scale is shown below:

The formula for this scale in relation to the major scale is 1, b3, 4, b5, 5, b7.

Relationships Between the Scales

Comparing the Pentatonic and Blues Scales to the Major Scale

The following chart shows how each of these scales relate to the major scale. This will make it easier to see the relationships between the scales.

Scale	1	2	b3	3	4	b5	5	6	b7	7
Major	x	x		x	x		x	x		x
Major Pentatonic	x	x		x			x	x
Minor Pentatonic	x		x		x		x		x
Blues	x		x		x	x	x		x

How the Major and Minor Pentatonic Scales are Related

Every major pentatonic scale also functions as a minor pentatonic scale starting on a different note. This is similar to the way the natural minor scale is derived from the major scale by starting on the sixth degree of the major scale. A minor pentatonic scale can be derived from the major pentatonic scale by starting on the fifth note in the major pentatonic scale and playing up an octave through the notes in the scale. For example, in C major pentatonic, the fifth note in the scale is an A. If you start on A and play through the notes in the C major pentatonic scale, you get the notes A, C, D, E, G, A. This is the A minor pentatonic scale. The notes in C major pentatonic are C, D, E, G, A, C. The notes in both scales are the same, but they start and end on different pitches. This is shown below:

How to derive a minor pentatonic scale from major pentatonic

The reverse is also true. A major pentatonic scale can be derived from any minor pentatonic scale by starting on the second degree of the minor scale.