The Nashville Number System...

...And Roman Numerals: Manage Chord Progressions Easily

The Nashville Numbering System is a method of denoting chord letter symbols by numbers, and it's one of the most important concepts taught in guitar lessons , really useful when dealing with chord progressions .

Roman Numerals System is another way for describing chord progressions, and it's a little more complex than the Nashville system because it uses uppercase and lowercase Roman Numbers.

In this tutorial, we're going to learn how to use both systems in a number of different situations. Are you ready?

Nashville Number System Vs Roman Numerals System

With the Nashville Number System, each chord of the scale is denoted by a number, depending on its position in the scale; have a look at the table below to get an idea:

Nashville Number System for the key of C and G
Key 1 2 3 4 5 6 7
C C Dm Em F G Am Bm/b5
G G Am Bm C D Em F#m/b5

As you can see, the numbers are always the same, while the key can change. If we say: a 1-4-5 song in the key of C, that's means C, F and G.

A 1-4-5 song in the key of G, is G, C and D.

On the web, there's a bit of confusion about the Nashville Number System, because some folks use Roman Numbers (I, II, III, IV, V, VI, VII) instead of 1, 2, 3, 4, 5, 6, 7, but the meaning is the same.

Actually, Roman Numbers are used in the Roman Numerals System, a more powerful way to the denote chord progressions, because, using lowercase and uppercase, it also provides information about the quality of the chords. Keep reading this article to learn about this.

Chords Degree Roman Numbers Chart - C and G Keys

Uppercase and Lowercase numbers

Roman Numbers can be written in uppercase or lowercase: this indicates the type of chord

  • The roman numbers for Major chords are written in uppercase (e.g. C, G, F)
  • The roman numbers for Minor chords are written in lowercase (e.g. Am, Dm, Em)
  • The roman numbers for Half-diminished chords are written in lowercase and with the ° symbol (e.g. Bm/b5)
  • We can have other symbol like the 7, for example, V7 denotes a Dominant chord in the fifth degree of the scale

In this way the Nashville Number System also shows the types of the song chords .
For example, the progressions I V vi vii° in the key of C is composed of these chords: C G Am Bm/Bf

Let's have a look at the chords table below. As you can see, the first chord of the scale is denoted with the roman number I, the second with ii, the third with III, and so forth. Pay attention to the uppercase and lowercase letters, and notice how major and minor chords are denoted. (the last chord, B, is a diminished chord).

Key I ii iii IV V vi vii°
C C Dm Em F G Am Bm/b5
G G Am Bm C D Em F#m/b5

How To Use Numbers Table

Let's say we take one of the more common progressions known as the I-IV-V , or the 1-4-5

Now suppose that your band mate says: "This song is I-IV-V"

We look at the table above, and immediately we know that:

  • In the key of G the chords are G C D
  • In the key of C, the chords are C F G

Easy, isn't? What you have to do is to understand the relationship between the chord and its scale degree number. In this way, you can denote chords with numbers and deal with progressions and chord substitution easier.

Another powerful device used to manage keys and chords (and much more) is the Circle Of Fifths , that deserves a separated tutorial.

Full Chart of keys and Roman Number System Numbers

Here below you find a complete chart showing the chords for all the keys .

This table is useful for knowing the chords in a key, and for transposing songs to another key .

As an exercise, try to find the chords for a I-IV-V song in F major key (solution at the bottom of the table).

Key I ii iii IV V vi vii°
C C Dm Em F G Am Bm/b5
G G Am Bm C D Em F#m/b5
D D Em F#m G A Bm C#m/b5
A A Bm C#m D E F#m G#m/b5
E E F#m G#m A B C#m D#m/b5
B B C#m D#m E F# G#m A#m/b5
F# F# G#m A#m B C# D#m E#m/b5
C# C# D#m E#m F# G# A#m B#m/b5
Cb Cb Dbm Ebm Fb Gb Abm Bbm/b5
Gb Gb Abm Bbm Cb Db Ebm Fm/b5
Db Db Ebm Fm Gb Ab Bbm Cm/b5
Ab Ab Bbm Cm Db Eb Fm Gm/b5
Eb Eb Fm Gm Ab Bb Cm Dm/b5
Bb Bb Cm Dm Eb F Gm Am/b5
F F Gm Am Bb C Dm Em/b5

The chords for a I-IV-V song in F major key are: F Bb C

Chords Degrees Functions

Each scale degree has a specific function in the rules of modern western harmony, and knowing how to combine them is the foundation of chords progression theory.

1st - Tonic

The I chord is the tonic chord , the root chord that all other chords are based off of, for now on we will use the key of C, so C will be our tonic chord.

2nd - Supertonic

The ii chord is the supertonic chord , which is one musical step above the tonic. The reason it is lowercase ii and not II is because the supertonic is often a minor chord. So in the key of C the ii chord is Dm.

3rd - Mediant

The mediant chord or the iii chord is also a minor and is the least used in most chord progressions. For the key of C the iii chord is Em and is a very weak chord compared to the others in the key.

4th - Subdominant

The IV chord is an F major which is known as the subdominant , it is very commonly used in many progressions and is one note below the dominant.

5th - Dominant

The V chord is the dominant chord , in this case a G. This chord is the second most important to the tonic or root chord of the progression, the dominant is used for tension as it often wants to resolve to the back to the tonic.

6th - Submediant

And then we have the vi chord, another minor chord and in this case Am. This is known as the submediant chord and provides a great contrast with the tonic.

7th - Leading Tone

And finally we have the vii chord, the leading tone . This chord is played in a variety of ways but always has the feel of needing to lead right back into the tonic, thus a leading tone.

Here is a helpful pdf reference sheet with the chords for all the major and minor keys .

Some popular songs denoted with the Roman Numerals System

So now that we have an understanding of chord progression basics and the Roman numbering system, let’s look at some of the more common and simple progressions out there. We will stay in the key of C for all examples.

I V (C G in the key of C)

beatles - yellow submarine chord progressions One of the most basic progressions used in folk music and reggae is I-V , or C-G.

These simple two chord songs can be very popular such as Camptown Races or Alouette and even the Beatles Yellow Submarine . Often a 7th is added to the V or dominant chord in these songs.

I IV I V I (C F C G C in the key of C)

bb king blues chord progressions Another popular progression is the blues progression I-IV-I-V-I and of course 7ths can be added to make C-F-C-G7-C.

There are so many variations on the blues progression and it doesn't take much skill to play around with it, early blues songs and early rock are based around blues progressions.

I bVII IV (C Bb F in the key of C)

boston more than a feeling chord progressions In Rock n Roll another common progression is I-bVII-IV, now that means the seventh chord is a major and flat.

C-Bb-F is used by Roy Orbison in You Got It and Boston in their song More Than A Feeling , in fact variations of this progression are well known by those in rock and pop rock.

I II IV I (C D F C in the key of C)

the Byrds Mr Tamburine Man chord progressions And finally another basic one is the pop rock lydian progression of I-II-IV-I , notice that the II is not a minor (ii) in this situation.

C-D-F-C was used in Eight Days A Week by the Beatles and Mr. Tambourine Man by the Byrds.

Now sometimes these chord progressions mentioned above are used for verses, choruses, and sometimes bridges.

Rarely is the same progression used throughout the entire song

However it is important to recognize these progressions.

After a while you will start to pick them out when you hear new songs, and even later still you will learn to appreciate subtle changes that songwriters make to common progressions .

That way they can create a song that will be liked, yet will still be a little different than the rest. Remember to always pay attention to the way in which various chords sound with each other, a tonic, dominant, and so on mean nothing if they cannot work off each other.

Each time you now learn a new chord, notice how it sounds when played before or after other chords you already know. Experiment as much as possible with chords , keys, and as many chord progressions as you can find!

Now you should have a good understanding of the these systems and its use in composition, improvisation and songs transposing. Below you find some useful resources for moving forward with the study of chord progressions:

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