What Does Diatonic Mean? Diatonic Scales Explained

In this guitar lesson you’ll learn what diatonic means, what diatonic scales are, and how they apply to guitar theory.

What is a diatonic scale?

A diatonic scale is a 7 note scale (heptatonic) containing 5 whole steps and 2 half steps in each octave.

Diatonic means “from a scale”, in particular a mode of the diatonic scale.

For example, the diatonic notes in the C major scale (C Ionian) are C-D-E-F-G-A-B.

If you introduce new notes or chords into a C Ionian melody or chord progression, it is no longer diatonic.

Diatonic chords are the chords built from diatonic scales.

For example, the 7 diatonic triads in the key of C major are:

C Major – D Minor – E Minor – F Major – G Major – A Minor – B Diminished

These chords are built by stacking notes from the diatonic scale in thirds. This ends up being every other note in the diatonic scale.

Continuing to use the C major scale, stacking notes from the notes C gives us C-E-G, which gives you a C major triad.

Stacking notes from the second pitch in the C major scale, D, gives us D-F-A, which gives you a D minor triad.

You can continue to do this with every pitch of a major scale, and you’ll build all of the triads from that scale.

As you stack more pitches, the chords remain diatonic, but become larger chords.

There are 7 modes of the diatonic scale. These modes are:

Diatonic defined simply means stemming from or relating to a musical scale/mode containing 5 whole tones and 2 semitones.

The most common example of this definition is the major scale. Learn about it and it’s formula here.

You can tell if a song is diatonic by looking at the notes in the melody and accompanying chord progression.

As long as the notes don’t break away from a parent diatonic scale, the song is considered diatonic.

It’s called the diatonic scale due to its ancient Greek definition meaning “through tones”.

A chromatic scale contains all 12 notes/pitches, played a half step/semitone apart.

A diatonic scale, on the other hand, uses a seven note scale sequence containing 5 whole steps and 2 half steps.