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How to Read Scale Diagrams

In this lesson we’re going to take a look at how to read scale diagrams. Scale diagrams are used all throughout this site to visually represent scale shapes and patterns on the guitar. It’s important to fully understand how to interpret them to get the most benefit from this site.

Scale Diagram Basics

First and foremost, scale diagrams are graphical representations of the guitar fretboard. These diagrams make it easy to visually connect the notes, shapes, and patterns represented graphically to the 3-dimensional guitar fretboard.

Fretboard Orientation

Scale diagrams are represented with two orientations, vertical (as if the guitar is standing straight up and down) and horizontal (as if the guitar is laying across your lap).

Scale diagram orientations

Strings and Frets on a Fretboard Diagram

As you would expect, scale diagrams for guitar include a visual representation for each of the six guitar strings. All fretboard diagrams on this site also show string thickness to make it easier to identify the correct string.

Fretboard diagram strings and frets

When in the vertical position, the low E string is the left most string and the high E is the right most string.

In horizontal orientation, the low E string is on the bottom of the diagram and the high E on top.

Frets are typically indicated by numbers on the left of vertical diagrams and on the bottom of horizontal diagrams. Corresponding inlays are also shown in the diagrams.

Scale Diagram Notation

At the heart of understanding scale diagrams is understanding the notation. Note markers are used to depict a number of different characteristics about a scale, from the notes that make up the scale to the intervals of the scale or fingerings for the scale.

Let’s start off with learning interval notation, as I believe it’s the most important to understand.

Interval Notation

Interval notation is used more than any other type of scale diagram notation on this site. It is absolutely essential to have working knowledge intervals on the guitar for it is the foundation of understanding what makes a scale/chord major versus minor versus diminished etc.

Interval markers are notated using numbers and symbols, as you can see in the diagram below.

Fretboard diagram of chromatic scale intervals
Interval notation

This diagram shows all of the intervals of the chromatic scale, which are all the intervals you’ll see on the guitar. Let’s go through each so you can understand what the symbols mean.

  • R
    • The R stands for root, which is the note upon which the scale is built. In the diagrams on this site, the root note is also highlighted using an orange note marker.
  • ♭2
    • The ♭ symbol indicates a flatted or minor interval. This interval is a minor 2nd.
  • ▵2
    • The ▵ symbol indicates a major interval. This interval is a major 2nd.
  • ♭3
    • Minor 3rd interval
  • p4
    • The p stands for perfect. This is a perfect 4th interval.
  • ♭5
    • Flat 5th interval
  • p5
    • Perfect 5th interval
  • ♭6
    • Minor 6th interval
  • ▵6
    • Major 6th interval
  • ♭7
    • Minor 7th interval
  • ▵7
    • Major 7th interval

Armed with the basic understanding of interval notation, you can now make sense of a major scale diagram like the one below.

Scale diagram interval notation
Position 1 of G Major Scale

Why Use Interval Notation?

Intervals are universal to a scale. In other words, the intervals of the major scale remain the same regardless of the key. So the G major scale contains the same intervals as the C major scale, the same as the D major scale and so on. Only the notes for each scale change.

Transposing scales on scale diagram using intervals
Intervals for G, C, and D Major Scales

This makes it much easier to transpose the scale to a new key. The intervals for the scale remain the same and they remain in the same location relative to the root note of the scale. Scale diagrams are an excellent way to show this relationship.

Note Notation

Note notation is more straightforward than interval notation in that it’s simply the note names that are indicated on the markers.

Note notation on a scale diagram
Scale Diagram with Note Notation

There are two symbols you will come across with note names:

  • #
    • Indicates a sharp note, or note that has been raised by 1/2 step
    • Indicates a flattened note, or note that has been lowered by 1/2 step

The root notes are highlighted via orange markers to make them easier to distinguish.

Check out the lesson Learning the Guitar Fretboard Notes for more information on note names.

Finger Notation

Scale diagrams using finger notation indicate which finger to use to fret a given note.

Finger notation on a scale diagram
Scale Diagram Using Finger Notation

Note markers are labeled as follows:

  • 1 – index finger
  • 2 – middle finger
  • 3 – ring finger
  • 4 – pinky finger

Occasionally, you may also see a T to indicate a note that should be fretted using the thumb, but this is not very common.

Again, the root notes are highlighted by the use of orange markers.

In the diagram below you can get a clear understanding of how all three types of notation relate and bring great understanding to scales on the guitar.

Interval, note, and finger notation on fretboard diagram
All 3 Forms of Scale Diagram Notation

Limitations of Scale Diagrams

While scale diagrams are extremely useful, they do have some limitations. Scale diagrams do not provide any information regarding how the scale should be played, note values, sequencing, etc. This type of information is better suited for guitar tablature. On this site you’ll often see guitar tablature included alongside scale diagrams.


Scale diagrams are very useful teaching tools. They provide an accurate visual representation of how notes and patterns appear on the guitar fretboard. However, it’s important to understand what the diagram is telling in order to get the most out of it. With this lesson, you should now have a solid understanding of scale diagram notation and be able to accurately interpret and make the best use of the diagrams on this site.

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