I, IV, V Chord Progression
♦ Learn what a I, IV, V Chord Progression is
♦ Learn the pattern for a I, IV, V Chord Progression
♦ Learn how to identify one
The I, IV, V chord progression is one of the most recognizable chord progressions in modern music. It's roots go back to early blues music and continues to thrive today across multiple genres.
It is first important to understand that a common way for musicians to refer to any chord progression is through the use of numbers. By using numbers instead of actual chord names (letters) they can communicate the structure of the chord progression.
That structure can then be applied to whatever key they decide to play the song in.
Quite often the numbers are notated as Roman Numerals, but standard numerals can also be used.
The numbers refer to the steps in a major scale like we learned in Lessons 53 & 54.
In the example of today's lesson, in a I, IV, V chord progression, the first, fourth and fifth steps of the major scale are the chords to be used for the structure of that chord progression.
A well known example of a number based system used in music is the "Nashville Number System" which was devised to assist studio musicians in a recording session. By writing chord charts with numbers instead of the actual chord names, the musicians could easily transpose the song to another key that might be more suited to a particular singer.
Look at the diagram of the major scale below. This is the scale you learned earlier.
The first, fourth and fifth steps in the major scale are highlighted. If, for example, we were told to play a I, IV, V chord progression in the key of "G", the root of our first chord (the "I" chord) would be a "G" which we know is on the 3rd fret of the 6th string. (Remember naming the notes on the 6th string?)
So we would know that the first chord in the I, IV, V chord progression, in this case, would be a "G" chord.
As you can see from the diagram, the fourth step in the major scale lands on the note that is adjacent to (on the 5th string) the first note. In the case of "G" being the first step, that would mean the fouth step is on the 3rd fret of the 5th string which, as we know, is a "C". So that means our "IV" chord is a C chord.
If you remember the "pattern" of the major scale you can see that the fifth step in the scale is two frets up from the fourth on the same string. To continue our example, if the four chord (IV) is "C", then the five chord (V) is two frets up from that which would make it a "D" chord.
So a I, IV, V progression in the key of "G" would mean that the structure of our song consists of the G (I), C (IV) and D (V) chords.
Although this may, at first, seem a little complicated, there is an easy way to figure out a I, IV, V chord progression anywhere on the neck of the guitar. Earlier you memorized the "pattern" of a major scale, now look within that scale at the "pattern" of the I, IV, V.
The shape of the "pattern" is always the same no matter where on the fret board you are. Look at Figure 1 on the right.
You will notice three examples of the I, IV, V "pattern" on the guitar. The middle example with the dots in yellow would be a I, IV, V in the key of "G", just like the scenario we just discussed. The "I" is on the 3rd fret of the 6th string so the progression is in "G" and the IV chord would be "C" and the "V" chord would be "D"
One of the other I, IV, V "patterns" (with aqua colored dots) starts with the I chord on the 8th fret of the 6th string. That would make the I chord a "C". In that case, the IV chord would be an "F" and the "V" chord would be a "G".
The final example with purple dots shows the I chord as the open 6th string which is an "E". Using the same "pattern", the IV chord would be on the open 5th string which is an "A", and the V chord two frets up which would be a "B" chord.
Remember back to the last lesson when you played "Before You Accuse Me"? That was a I, IV, V chord progression in the key of "E" so it consisted of the E, A and B chords.