The 12 Bar Blues Form

What is the Blues Form?

As I mentioned in about the blues, a song form is a structure, or a kind of formula, for a piece of music. The blues form is a specific song structure used in the blues as well as other styles inspired by the blues like rock, jazz, R&B, etc.

Applying the I, IV, and V Chords

The blues uses the I, IV, and V chords throughout the song form. If you’re unfamiliar with the concept of the I, IV, and V chords, make sure you go through that lesson before continuing.

There are many variations of the blues. First I’m going to teach you the most common form that confuses students the least. Later in the lessons we’ll look at the many other variations.

The 12-Bar Blues Form

The most common form of the blues is a 12-bar pattern of chord changes. That is, a repeated twelve-bar chord progression. This is called “12-Bar Blues”.

You should remember a bar is the same as a measure. Most often in blues you will count 4 beats to each bar – 4/4 time.

In a blues song this 12-bar cycle gets repeated over and over through the course of the tune. A blues song might play through it 20 times. It will depend on the specific song.

The blues can be played in any key. In whatever key you are in, 12-bar blues uses the same basic sequence of I, IV, and V chords. It is most easily thought of as three 4-bar sections – the first 4, the middle 4, and the last 4 bars.

The first 4 bars just use the I chord - I, I, I, I.

The middle 4 bars go IV, IV, I, I.

And the last 4 bars go V, IV, I, V. Then you repeat the whole thing again.

So, the basic 12-bar sequence looks like this:

The blues form - I-I-I-I-IV-IV-I-I-V-IV-I-V

Plugging In the Chords from a Key

To get the blues chord progression for the blues in A, we take the I, IV, and V chords from the key of A. That means A is I, D is IV, and E is V. Then, we plug those three chords into the corresponding places in the blues form. We end up with this set of chord changes:

The blues form in A - A-A-A-A-D-D-A-A-E-D-A-E

For the blues in any other key, we’d do the exact same thing. Blues in C would plug in the chords C, F, and G into the 12-bar blues structure. Blues in E would use E, A, and B. And, so on. There are 12 major keys; you can play the blues in any one of them.

Playing the Blues Form

The first step in learning to play the blues is getting comfortable with where the chords change. You need to memorize and completely internalize this sequence of chords. You can’t ever get lost wondering to yourself, “What chord is next?” With enough time and practice, you'll just hear and feel what the next chord change is. In the beginning you may have to really concentrate on the changes.

The Blues Form Exercises

In the blues form exercises we’ll outline each chord with its root note. You should be able to do this by yourself with a metronome and never miss a chord. You might record yourself to make sure you aren’t skipping any!

Once you have that down, we’ll apply more notes to the same set of chords. That’s when it’ll start to sound more like the blues and get more fun. Don’t fall asleep on me!