Guitar Fret Intervals
How intervals work on the fretboard

This lesson on fret intervals leads on nicely from the guitar fretboard lessons and learning where all the notes lie (part 1 and part 2).

Now we're going to look at learning the intervals on your guitar's fretboard. Intervals are basically the spaces between two or more notes and a bunch of intervals between several notes creates a scale.

It's not just about creating scales though - knowing how intervals work on the fretboard will make constructing chords (without needing a chord chart) ten times easier, plus, you'll eventually be able to hear two chords in a song and know exactly which root note interval was used (or at least have a pretty good idea!)

Fret interval basics - whole steps and half steps

As you get into more advanced guitar theory, you'll hear people talk about "whole steps" and "half steps". Well, what they're referring to are intervals - the spacing between notes (or chords).

See the diagram below for an explanation of these "steps"...

So if we were to move from the note G at the 3rd fret up a whole step we would end up on the note A at the 5th fret.

If we were to move from the note A at the 5th fret down a half step we would end up on the note Ab at the 4th fret.

Obviously, when we want to play a scale we'll want to use more than one string for more economical movement of the fingers, so we need to know these intervals vertically as well as horizontally...

Fret intervals across more than 1 string

So, let's look at a few diagrams and see how intervals look in relation to the next string up. Grab your guitar and play these positions so you can hear the sound of the interval.

Half step / semi-tone from low E to A string

Whole step interval from low E to A string

Both these interval relationships work for the bottom 4 strings - E-A, A-D and D-G. However, because the B string is tuned differently in relation to the G string, we have to compensate by adjusting the interval space on the fretboard:

Whole step from G to B string

Then it's back to the same fret spacing as before between the B and high E string...

Half step / semi-tone from B to high E string

Whole step from B to high E string

Now for larger intervals!

In the following diagrams, the 2 red squares are the same note and interval, just on different strings...

Major 3rd interval

Incidentally, that was a major 3rd interval because the yellow square represents the root and the red squares are where the 3rd note would lie in the major scale.

Some more intervals to learn and visualise...

Minor 3rd interval

4th interval

Now, some things to note...

• These vertical intervals work with the bottom 3 strings, but because of the tuning of the B string on your guitar, the actual fret interval changes (the step interval remains the same though).
  
  

• e.g. a 2 whole step interval from the G note on the D string (5th fret) would end up on fret 4 of the G string (the note B). Use the diagrams above as visual guides for those bottom 3 strings.
  
  

• Try experimenting with "your own" intervals. Listen to the sound of the interval, one note to the next. Really hear it and get to know what that interval sounds like in relation to how it looks on the fretboard!

That last bullet point is the most important - learn to visualise on the fretboard from what you hear. Simply spend time observing, and listening.

So let's say we're playing a chord with its root note on the A string - we know how the interval we want looks on the next string up, but we could find a lower voicing on the string below if we can find that same interval.

Let's just look at some more diagrams!...

Major 3rd interval

Minor 3rd interval

So again, the red squares are exactly the same notes and intervals, but this time they're an octave apart (same note but a lower/higher version).

The more intervals you can memorise and visualise, the easier and faster you will be able to pick out that next chord/note. In time, and the more you train your ear to the sound of different intervals, you will be able to hear them in your head and see them on the fretboard in more than one location.

Notice how in those diagrams above, this all goes hand in hand with part 2 of the fretboard lessons - string relationships.

Making a scale from intervals

If we look at the intervals of the major scale (also the first mode - Ionian)...

1 - W - 2 - W - 3 - H - 4 - W - 5 - W - 6 - W - 7 - H - 1

If we spread this across the 6 strings as standard, we get the following scale shape based on the intervals...

A deeper understanding of fret intervals in scales

Go to part 2 >