A pentatonic scale, as the name implies, has only five notes. It can also be major or minor. Pentatonic scales are great for improvising over many standard chord progressions.

Major Pentatonic Scale:

To make this easier to explain (and understand), instead of using note names I’ll refer to scale degree numbers 1-7 of the major and minor scales. This makes it easy to transpose the scale into different keys.

Ok, the major pentatonic scale is scale degrees 1, 2, 3, 5, 6 of the regular major scale. It’s basically a major scale without 4 and 7. Notice how when you remove degrees 4 and 7 from the major scale there are no more half steps. For this reason pretty much any note in the major pentatonic scale sounds good over a major chord progression.

G major pentatonic scale:

Minor Pentatonic Scale:

The minor pentatonic scale is 1, 3, 4, 5, 7 of the natural minor scale. That is, a natural minor scale without degrees 2 and 6. Sometimes it’s easier for me to think of a major pentatonic scale that starts and ends on degree 6.

E minor pentatonic scale:

Improvising Using the Pentatonic Scale:

The easiest way to improvise over a chord progression is to use a pentatonic scale. Given, after a while you’ll probably want to add notes outside of the pentatonic scale, but it’s a great foundation to start. All you have to is figure out if the song is in a major or minor key. You can do this by listening to see if it sounds “happy ” or “sad ” and using the appropriate pentatonic scale assuming you know what key it’s in.

If you don’t know what key the song is in try to figure out the tonic note, that is the note that the song always returns to and the note it generally ends on. If you know the tonic, then you know what key it’s in. Fiddle around with both of the pentatonic scales and see what sounds best. Sometimes you can use the minor pentatonic scale over a song in a major key and vice versa, giving your solo and different feel. Once your fluent in your pentatonics, you can start to have fun with it and try adding notes outside of the scale.