Roman numeral analysis

In music, roman numeral analysis is the use of roman numeral symbols in the musical analysis of chords. Arabic numerals with carets are used to designate scale degrees themselves, while the roman numeral refers to a chord built upon that scale degree.

Roman numeral analysis symbols
Roman Numeral	Triad quality	Example (tonic)
Uppercase	Major triad	I
Lowercase	Minor triad	i
Lowercase o	Diminished triad	io
Uppercase +	Augmented triad	I+

Developed in the 19th century for the purpose of harmonic analysis, "the roman numeral system is limited to classical harmony (closely related diatonic chords and key centers)," and alternatives include the functional hybrid Nashville number system and macro analysis.

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