Changing Diatonic Chords to their Degree Names (4 Note Chords - Major) / Music Theory Lesson

Author: sleepfreaks

Degree Names for 4 Note Chords

In continuation of triads, we will be taking a look at 4 note diatonic chords (7th chords)
and changing them with their “roman numeral (degree name)” equivalents.

4 note chords will show up frequently when analyzing chords so be sure to master this content.

By knowing the materials discussed in our 21st article on music theory, this article should be much easier to understand.
If you haven’t done so, please check out this article first.



The chart we will use for analysis can be downloaded from the link below.

The Rules with Diatonic Chords are the same as Triads

First, lets take a look at the major diatonic 7th chords.


Like the triads, memorizing all of these is a lot of work.
However, you may have already realized this, but the 7th chords and triads work follow the same rules.

    • Key = C Major


    • Key = D Major


In either key, we can see that they both follow the order of
Major 7th / minor 7th / minor 7th / major 7th / dominant 7th / minor 7th / minor 7th b5.

Just like with triads, you can easily move between keys within your DAW by knowing this information.


Lets use this rule to our advantage and change the degree of each scale with it’s roman numeral equivalent.

Applying Roman Numerals to a Scale

In the same way as we did in our article with triads, lets apply roman numerals in order starting from the first note of a scale.



Lets create diatonic chords from here. For more info check out our 18th article.
The type of chord will be depicted next to the roman numeral.


This completes it.
By using roman numerals to designate chords, you can input the notes of whatever major scale is selected to easily find out the diatonic chords (7th) of the key.

  • You may see a △ next to major or ⅲ for minor using degree names. For the purpose of these tutorials we will stick to the style shown above.

Using Degree Names

Lets try changing the scale to the Key=A major.



By using what we have learned up until this point, its very easy to do.

In addition, the chords would be named as shown below:

  • Imaj7 = one major 7th
  • IIm7 = two minor 7th
  • IIIm7 = three minor 7th
  • IVmaj7 = four major 7th
  • V7 = five 7th (dominant 7th)
  • VIm7 = six minor 7th
  • VIIm7b5 = seven minor 7 flat 5

Last, we have included a list of major diatonic chords (7th) including roman numerals so please check it out from the link below.


In our next article we will be looking at some simple analysis and modulation
using 7th chords, non diatonic chords, and more.

Your understand will begin to deepen and go beyond triads so stay tuned!

Article Writer: Kazuma Itoh

講師 伊藤
After moving to the USA at 18 years of age with a scholarship from Berklee, he completed a 4 year study focused on song writing and arranging there.
Using this knowledge, he works across a variety of fields from pop music, film music, and more.