Roman numerals are named based on the scale degree they're built on. An upper case Roman numeral means the chord is major. A lowercase roman numeral means it is minor. Roman numerals with an 'o' superscript are diminished.

In minor, the V and viiº use the raised 7th degree.

How-To Video: Roman Numeral Construction & ID

Figured bass is used to indicate what member of the chord is in the bass.

• If the Root is in the bass: There is no figure on the Roman numeral (e.g. just I)

• If the 3rd is in the bass: Add a "6" to the Roman numerals

• If the 5th is in the bass: Add a 6 and 4 to the Roman numeral

When you add a 7th to the Roman numerals above, you get the following 7th chords:

• M7 = Major 7th (Major triad + M7th)

• Mm7 = Dominant 7th chord (Major triad + m7th)

• mm7 = Minor 7th (minor triad + m7th)

• hd7 = Half-Diminished 7th (diminished triad + m7th)

• dd7 = fully diminished 7th (diminished triad + d7th)

* Note that the only Mm7 chord is the 7th chord built on 5.