Roman Numeral Analysis

Roman numerals are commonly used in music to reference the various degrees in a scale.

You just need to know how to count to seven in roman numerals: I, II, III, IV, V, VI, and VII.

This gives us an easy way to refer to each note in a scale without knowing which scale/key we're talking about. For example, in the key of C Major, I would refer to C, II would refer to D, and so on. But in D major, I would refer to D, II would refer to E, and so on.

Roman numerals are used (instead of 1, 2, 3, etc.) so that it's clear we're talking about the notes in the scale instead of, say, the fingering of the piece. This different way of counting is only used for this purpose.

When talking about music theory, it's extremely helpful to think in this way. That's because the I note is our root note, which is much clearer than trying to remember which note is the root at any given time.

Each of the seven steps represent one of the seven degrees of a scale. These more formal names for the degrees are less commonly used, exactly because roman numerals are so much easier to reference:

• I: Tonic
• II: Supertonic
• III: Mediant
• IV: Subdominant
• V: Dominant
• VI: Submediant
• VII: Subtonic

Often, we want to refer to an entire chord (not just a single note). Thankfully, roman numeral analysis also gives us a way to describe chord qualities.

• Uppercase numerals describe major chords
• Lowercase numerals describe minor chords

We also have shorthand for various chord qualities:

• + (the plus symbol) means "augmented"
• ° (the degree symbol) means "diminished"
• Ø (a zero with a slash) means "half diminished"

Putting it all together, here are some examples in the key of C Major:

• iii Minor third (E Minor)
• V Major fifth (G Major)
• vii° Diminished seventh (B diminished)

One of the most common ways to use roman numeral analysis is with major and minor triads. When we look at any given scale, there is a triad chord associated with each note in the scale that helps build chord progressions.

• In major scales, the triad chord progression is I, ii, iii, IV, V, vi, vii°
• In minor scales, it is i, ii°, III, iv, v, VI, VII

To see each of the scales' triad chords (and learn to play them with Chordzy), see the links at the bottom of this article.

To describe a seventh chord (aka a four-note chord), a superscript seven ⁷ is added.

You'll also see a superscript ^M used to indicate a major seventh.

Finally, you'll occasionally see chord inversions indicated with roman numeral analysis, called figured bass.

The number in the superscript will instead refer to the inversion:

• No inversion: triads have no superscript; sevenths have a seven I⁷
• First inversion: triads use I⁶ and sevenths use I⁶₅
• Second inversion: triads use I⁶₄ and sevenths use I⁴₃
• Third inversion: not applicable to triads; sevenths use I⁴₂

If you have a hard time remembering these numbers, you just need to count the intervals. Consider the C Major Triad, First Inversion (E-G-C). There are 6 steps between E and C, thus the six superscript. For the second inversion (G-C-E), and 6 steps again from G to E... but 4 steps from G to C. So in this case we use 6 and 4 for clarity.