Ionian Mode: Everything You Need to Know About Ionian

Everything you need to know about Ionian

The Ionian Mode is the first mode of the Diatonic Major Scale. Let’s look and listen to it with a bit more detail.

The Ionian mode is often described as the white keys on the keyboard from C-C’. This gives us the following intervallic series:


*w=whole step // h=half step*

And the notation looks like this:

everything you need to know about ionian

That’s the notes C D E F G A B C’ with no alterations (sharps or flats).

Since we base scales degrees on the Major Scale, and the Ionian mode is made up of the same notes as the Major Scale, we simply have the scale degrees of:

1        2        3        4        5        6        7

Another way to write the scale degrees is:

  • Root (as is always the case)
  • Major Second (2 semitones above the root)
  • Major Third (4 semitones above the root)
  • Perfect Fourth (5 semitones above the root)
  • Perfect Fifth (7 semitones above the root)
  • Major Sixth (9 semitones above the root)
  • Major Seventh (11 semitones above the root)
Let’s listen to the C Ionian mode against a droned C note:

The modal chords of the Ionian mode

The Ionian mode yields one triad and one tertian seventh chord:

  • Major triad                       1        3        5
  • Major seventh chord    1        3        5        7

Other common chords include:

  • Sus2                                     1        2        5
  • Sus4                                     1        4        5
  • 6/9                                        1        3      (5)      6        9
  • Maj7sus4                           1        4        5        7

Along with all the extensions beyond the major seventh chord, notably:

  • Maj9                                     1        3        5        7        9
  • Maj13                                   1        3        5        7        13

Note that the 4th/11th scale degree of the Ionian mode is an “avoid note.” This is because the major third clashes with the perfect fourth (minor second interval). By the same token, the major third clashes with the eleventh (flat ninth interval).

That being said, the 4 and 11 can still find their way into chords (sus4 and extensions) and can be included for purposeful dissonant effect. Of course, “avoid” in “avoid note” is only a suggestion. It’s dissonant with the third, but if you like, play it!


In a major key, the tonic coincides with the Ionian mode. Once again, the Ionian mode is made up of the same notes as the Major Scale!

This makes the Ionian mode very useful in creating major key harmonies. If an entire chord progression is in the key of G Major, for example, then we may easily build melodies out of the G Ionian mode! Just watch out for the 4th degree avoid note, in this case, C!

Ionian’s Characteristic Tones

When looking for a mode’s characteristic tone(s) (the tones that give it its flavour and differentiate it from other modes), it’s a good idea to first look at the tritone intervals and half step intervals. It’s also very important to look at the quality of the third (is it minor or major?)

The Major Scale’s modes each have two half step intervals and one tritone interval.

One tritone interval could mean two tritone intervals. For example, B-F is a tritone and F-B is a tritone (completing the octave). Most of the time we’ll look for the [one] tritone interval in the Major Scale modes.

It’s tough to give Ionian characteristic tones since it’s so often the center of tonal harmony and every tone seems important.

The perfect fourth is often considered an “avoid note” in Ionian (in functional harmony) since it creates a flat ninth interval with the major third. Oddly enough, the fourth be a characteristic tone since it is part of the tritone interval (with the major seventh) and it creates a half step interval with the major third.

The other half step interval is between the major seventh and the root.

So we’ve deduced that the major seventh and the major third are important. We can classify them as “characteristic tones,” even though they are shared with the Lydian Mode (and some modes from scales other than the Major Scale).

I tend to think of Ionian as “too general” (along with its natural minor, Aeolian) to really pin it down with characteristic tones.

That being said, I’d argue that the “avoid note” perfect fourth would be Ionian’s characteristic tone (as dissonant as it is against the maj7 chord). This is the differentiating tone between Ionian and Lydian.

Ionian’s Modal Chord

Once again, the general tonal center Ionian provides makes it difficult to make it too “interesting” in modal chord terms. But because it plays such a huge role in major key centers, we can give it reigns to a common chord of only 4 notes. The Major Seventh Chord!

1        3        5        7

Many other modes will create a major seventh chord, but Ionian is so common, that I think it’s safe to give it “first dibs.”

I know, I know. This is a poor argument, but there’s really nothing that “stands out” about this mode. It’s almost too engrained in our musical ears, in a way…

The importance of the Ionian Mode

The Ionian Mode, the Major Scale, the Diatonic Scale. Whatever you like to name it, it’s arguably the most important scale to know! I argue that point here.

The Ionian mode:

  • creates melodies based on the tonic in a major key chord progression.
  • has only unaltered scale degrees.
  • is the base for alterations in other modes.
  • is a diatonic scale (the most commonly harmonized scale).

Practicing Ionian And Modal Harmony

As with all modal harmony practice, I prefer the pedal point method.

Pedal (drone a constant tone) the root of Ionian, if you have a polyphonic instrument. And go through each of the scale degrees to hear the intervals they create against the root.

1       2       3       4       5       6       7

If you have a monophonic instrument, try alternating between the root and each scale degree, one-by-one, to get a sense of each distinct interval.

I prefer the piano for these exercises.

Once again, pay special attention to the characteristic tone and the avoid note, which in Ionian’s case is the 4. Also be aware of the major third, since it gives Ionian its major quality.

Next, try droning the “modal chord.” In Ionian’s case, the major seventh chord. Of course, this is only possible on a monophonic instrument. Although, arpeggios could work on monophonic instruments.

Go through the same exercise of relating every scale degree to the chord and listen to how each one compares, paying attention to the characteristic tone and avoid note.

Next, cycle through intervals played in unison with a droning root note. Practice playing and hearing all the second, third, fourth, fifth, sixth, and seventh intervals present in Ionian compared to the root pedal point. Pay special attention to the half step intervals against the root and the tritone intervals against the root.

Finally, have some fun creating modal chords with any of the Ionian notes played with its root!

An example could be stacking fourths. Stacking fourths is a common way to express openness and modality. In Ionian’s case, a stacked fourth tetrad would be:

1       4       7       3′

Writing and Composing with Ionian

A quick note on tonal harmony vs. modal harmony

When composing with tonal harmony, we have “circular cadences.” Resolutions that often happen while moving around the circle of fifths (or fourths, depending on how you look at it).

For example, the iii-vi-ii-V-I chord progression in C Major would be:

  • Emin7
  • Amin7 (or A7 as a common alteration)
  • Dmin7
  • G7
  • Cmaj7

Those chords’ roots move circularly counter-clockwise through the circle of fifths.

This is tonal (functional) harmony.

Modal harmony has linear, or lateral cadential movement. Often times the best cadential chord is built on the second or seventh scale degree of the mode.

In modal harmony, we must take great care as to not seek out the dominant V chord, or to play too many chords other than the tonic. Doing so will result in our ears hearing tonal harmony, as it’s so commonly used in music.

We must reference the tonic chord very often to ensure that we are indeed in that specific mode! In fact, some modal works contain static harmony, where the underlying chord stays the same throughout the piece.

In modal harmony, we don’t absolutely need to use all the notes in the mode, but it helps to further specify, unambiguously, which mode we’re in. For example, Ionian without its perfect fourth is the same as Lydian without its augmented fourth.

Ionian’s modal cadences

The modal cadences in Ionian are tricky since the Ionian mode is the same scale as the Major Scale, and therefore the basis of functional tonal harmony.

We mention in the Mixolydian article that the V (dominant) chord is the chord that wants to resolve the most to the major tonic I chord (the Ionian chord). But in modal harmony, we don’t want that, as it takes us out of the modal/lateral movement and puts us into the tonal/circular movement.

Instead, we want to look step-wise to find the most cadential chords. The more cadential chords are chords that:

  • are major in quality.
  • contain the characteristic note.
  • do not contain a tritone interval (making them sound dominant)

Note that chords a third away from a mode’s root do not provide much tension and are often merely heard as “changes of color” (especially in tertian harmony).

Note also that chords a fourth/fifth away tend to lead us out of modal harmony and back toward the circular nature of tonal harmony.

So the most cadential chord in Ionian modal harmony is the ii(min7) (Dorian chord).
  • It’s a whole step away (lateral movement)
  • The minor third weakens its cadential strength
  • But it contains the characteristic tone as its minor third degree

The other most cadential chord would be the vii(half-diminished). However, due to its tritone interval, we’d like to avoid it in order to stay within modal harmony.

Of course, this is all just for your information and not set in stone, if it sounds good, play it!

In Closing,

I invite you to write a song based on the Ionian mode. For more information, check out my article on writing and playing modally.

Chances are, even if you don’t know the mode, you’ve been using it plenty in writing and playing music.

Let me know what you come up with while writing with the Ionian mode! And if there’s anything else you’d like to add to the discussion of the Ionian mode, please leave a message in the comment section!

As always, thank you for reading and for your support,