To learn music theory as a guitarist, start with the notes on the fretboard, then the intervals, then the chord formulas, then the major scale and its chords, and then the circle of fifths. Learn each idea on the guitar, not just on paper, so the theory is in your fingers, not just in your head.
How do you learn music theory as a guitarist?
To learn music theory as a guitarist, start with the notes on the fretboard, then the intervals, then the chord formulas, then the major scale and its chords, and then the circle of fifths, learning each idea on the guitar, not just on paper, so the theory is in your fingers, not just in your head. The theory is the map, and the guitar is the territory, and a player who learns the theory on the guitar will understand it, because the fingers feel the intervals, and the ears hear the chords, and the map and the territory match. The order matters: the notes on the fretboard come first, because they are the foundation, and the intervals come next, because they are the distances between the notes, and the chord formulas come next, because they are the intervals that make the chords, and the major scale comes next, because it is the notes that make the key, and the circle of fifths comes last, because it is the keys, and how they relate. Each idea builds on the last, and the player who skips an idea will not understand the next, because the next assumes the last. The fretboard note finder shows the notes, and the interval calculator shows the intervals.
How guitar music theory works
Guitar music theory works because the guitar is a pattern, and the theory is the pattern, and the two match. The fretboard is a grid, with the notes repeating every twelve frets, and the intervals are the distances, in semitones, between the notes, and the chords are the intervals, stacked, root, 3rd, 5th, and the scales are the intervals, in order, whole, whole, half, whole, whole, whole, half, for the major scale, and the circle of fifths is the keys, arranged by perfect 5ths, so the theory is the pattern, and the guitar is the pattern, and learning one teaches the other. The theory is learned on the guitar by playing it: the intervals are played, on two strings, and the ear hears the distance, and the chord formulas are played, as chords, and the ear hears the chord, and the major scale is played, as a scale, and the ear hears the key, and the circle of fifths is played, as chord progressions, and the ear hears the keys, and the theory is in the fingers, and in the ears, not just in the head. The C major scale and the G major scale are the scales most guitarists first learn theory on, and the key of C major is the key most theory is learned in.
Worked example — learning the major scale as a guitarist. Play the C major scale on the guitar, starting on the 5th string at the 3rd fret, which is C, and playing C, D, E, F, G, A, B, C, ascending, and listening for the pattern, whole, whole, half, whole, whole, whole, half, which is the major scale. The intervals are C to D, a major 2nd, two semitones, D to E, a major 2nd, two semitones, E to F, a minor 2nd, one semitone, F to G, a major 2nd, two semitones, G to A, a major 2nd, two semitones, A to B, a major 2nd, two semitones, and B to C, a minor 2nd, one semitone, and the pattern is the major scale, and the ear hears it, and the fingers feel it. The chords of C major are C, Dm, Em, F, G, Am, Bdim, which are the I, ii, iii, IV, V, vi, vii chords, and the I–V–vi–IV progression in C major is the progression the theory is built on.
How to practise learning music theory as a guitarist
Practise learning music theory on the guitar, one idea at a time, playing each idea, and hearing it, so the theory is in your fingers, not just in your head.
- Learn the notes on the 6th and 5th strings, and test yourself with the fretboard note finder, naming the note at a random fret.
- Learn the intervals, major 2nd, major 3rd, perfect 5th, and octave, by playing them on two strings, and naming them by their sound, with the interval calculator.
- Learn the chord formulas, major, minor, and dominant 7th, by playing the chords, and naming their notes, with the chord finder.
- Play the C major scale and the G major scale, and name the chords of each key, and play the I–V–vi–IV progression in C major.
- Learn the circle of fifths, with the circle of fifths tool, and play the chords of each key, in order, around the circle.
Common mistakes
- Learning theory only on paper — Theory learned only on paper is not understood, because the fingers have not felt it, and the ears have not heard it, and the theory is in the head, not in the hands. Learn the theory on the guitar, playing each idea, and hearing it, so the theory is in the fingers, and in the ears.
- Skipping the basics — The theory builds on itself, and skipping the basics, the notes and the intervals, will make the chords and the scales incomprehensible, because they assume the basics. Learn the notes first, then the intervals, then the chords, then the scales, and then the circle of fifths, in order.
- Learning too much at once — The theory is a lot, and learning it all at once will overwhelm the brain, and none of it will stick. Learn one idea at a time, until it is understood, and then learn the next, and the ideas will build on each other, and the theory will be learned.
Quick reference
This table shows the five steps to learning music theory as a guitarist, with the idea and what to learn in each step, so you can see the order at a glance. The notes come first, then the intervals, then the chords, then the scales, and then the circle of fifths, and each step builds on the last.
| Step | Idea | What to learn |
|---|---|---|
| 1 | Notes on the fretboard | 6th and 5th strings, then all strings |
| 2 | Intervals | Major 2nd, major 3rd, perfect 5th, octave |
| 3 | Chord formulas | Major, minor, dominant 7th |
| 4 | Major scale and its chords | C major, I, ii, iii, IV, V, vi, vii |
| 5 | Circle of fifths | Keys, sharps, flats, relatives |
Use the table to learn music theory: start at step one, learn the notes, and move to step two only when step one is understood, and so on, until step five, the circle of fifths, is understood. When you can play the theory, not just recite it, you have learned it, and the guitar will make sense.
Frequently asked questions
How do I learn music theory as a guitarist?
Start with the notes on the fretboard, then the intervals, then the chord formulas, then the major scale and its chords, and then the circle of fifths, learning each idea on the guitar, not just on paper, so the theory is in your fingers, not just in your head.
Do I need music theory to play guitar?
No, but it helps, because theory explains why the chords work, and why the progressions sound good, and it lets the player transpose, improvise, and write songs, instead of just copying shapes. A player without theory can play, but a player with theory can understand.
What is the first theory idea a guitarist should learn?
The notes on the fretboard, because they are the foundation, and every other idea, intervals, chords, scales, and keys, assumes the notes. Learn the notes on the 6th and 5th strings first, because they are the roots of the barre chords.
How long does it take to learn music theory?
A few months, with daily practice, one idea at a time, because the theory builds on itself, and each idea must be understood before the next is learned. A few minutes a day, every day, will teach the theory, one idea at a time.
Can I learn music theory without reading sheet music?
Yes. Guitar theory can be learned on the fretboard, with the notes, the intervals, and the chords, without reading sheet music, because the guitar is a pattern, and the theory is the pattern, and the pattern can be seen on the fretboard, not just on paper.