Roman numeral harmonic analysis shows how chords work inside a key. This cheat sheet helps students label chords, identify inversions, and understand common progressions in tonal music. It is especially useful for analyzing chorales, classical excerpts, pop progressions, and four-part writing.
The reference organizes the topic into clear visual cards for quick study and classroom use.
The most important ideas are key, scale degree, chord quality, inversion, and harmonic function. Uppercase Roman numerals usually show major chords, lowercase Roman numerals show minor chords, and diminished symbols show diminished chords. Figured bass numbers such as 6, 6/4, 7, 6/5, 4/3, and 4/2 show which chord tone is in the bass.
Tonic, predominant, and dominant functions explain why progressions sound stable, moving, or tense.
Key Facts
- In a major key, the diatonic triads are I, ii, iii, IV, V, vi, and vii°.
- In a natural minor key, the diatonic triads are i, ii°, III, iv, v, VI, and VII.
- In harmonic minor, scale degree 7 is raised, so the dominant chord is usually V and the leading-tone chord is vii°.
- Uppercase Roman numerals label major chords, lowercase Roman numerals label minor chords, and the symbol ° labels diminished chords.
- Triad inversions are root position with no number, first inversion as 6, and second inversion as 6/4.
- Seventh chord inversions are root position as 7, first inversion as 6/5, second inversion as 4/3, and third inversion as 4/2.
- The basic harmonic functions are tonic for rest, predominant for motion away from tonic, and dominant for tension that resolves to tonic.
- Common cadence patterns include authentic cadence V-I or V-i, half cadence ending on V, plagal cadence IV-I, and deceptive cadence V-vi or V-VI.
Vocabulary
- Roman numeral analysis
- A system that labels chords by their scale degree and function within a key.
- Scale degree
- A numbered note of a scale, such as 1 for tonic, 5 for dominant, and 7 for leading tone.
- Figured bass
- A set of numbers that shows the intervals above the bass note and helps identify chord inversion.
- Inversion
- The position of a chord when a note other than the root is the lowest sounding note.
- Harmonic function
- The role a chord plays in a progression, commonly tonic, predominant, or dominant.
- Cadence
- A harmonic ending or stopping point that creates closure or pause in a musical phrase.
Common Mistakes to Avoid
- Confusing the bass note with the root is wrong because inversion depends on the bass, while the Roman numeral name depends on the chord root.
- Using uppercase and lowercase randomly is wrong because chord quality must match the actual notes, such as V for major and v for minor.
- Forgetting to raise scale degree 7 in harmonic minor can lead to labeling V as v, even though tonal minor often uses a major dominant chord.
- Labeling every 6/4 chord as a normal tonic chord is wrong because cadential 6/4 chords often function as part of the dominant, such as I6/4 to V.
- Ignoring accidentals outside the key is wrong because altered notes may create secondary dominants, borrowed chords, or changed chord qualities.
Practice Questions
- 1 In C major, identify the Roman numeral for the chord F-A-C.
- 2 In G major, identify the Roman numeral and inversion for the chord B-D-G with B in the bass.
- 3 In A minor using harmonic minor, identify the Roman numeral for the chord E-G#-B-D.
- 4 Explain why the progression ii6-V7-I creates a strong sense of motion toward the tonic.
Understanding Roman Numeral Harmonic Analysis
A Roman numeral label is a summary of several musical facts at once. To choose one accurately, first establish the key from the notes, the key signature, and the feeling of arrival. Then stack notes in thirds above the chord root, even when the notes appear in a different order on the staff.
This prevents a common mistake, which is naming the bass note as the root. After finding the root, count its place in the scale and check the chord tones.
The numeral describes the chord's job in that key, not simply its letter name. A D major chord, for example, has a different label in G major than it does in D major.
Inversions matter because bass lines strongly shape what listeners hear. Two chords can contain the same three notes but create different motion when a different note sits at the bottom. First inversion often makes the bass move smoothly by step.
Second inversion is less stable in common practice music. It often appears as a passing sonority, a neighbor sonority, or near a cadence before a dominant chord. Students should identify the bass only after identifying the root and quality.
The figures are not extra chord names. They tell the intervals above the bass, which is why the same Roman numeral can have several figured forms.
Harmony becomes clearer when chords are studied as groups that lead somewhere. Tonic area includes chords that prolong a sense of home, even if the main tonic chord is not sounding. Predominant chords prepare the dominant area.
Dominant harmony contains a strong pull because its leading tone tends to rise toward the tonic note, while another active note often moves downward by step. In four-part writing, these tendencies guide good voice leading.
Keep common tones when possible, move active notes in their expected direction, and avoid large leaps unless the line remains singable. Parallel fifths and octaves are watched closely because they make independent voices sound fused together.
Real music does not always stay within the notes of one scale. A composer may temporarily use a chord that points toward a chord other than the tonic. This is called an applied dominant.
It creates a brief spotlight on the upcoming chord without necessarily changing the overall key. Minor keys create another important choice. The natural minor scale gives a weaker dominant, so composers often raise scale degree seven to produce a stronger pull back to tonic.
When analyzing, mark accidentals carefully and listen for arrivals. A convincing analysis explains the notes, the bass, and the direction of the phrase. If a label fits the spelling but not the musical motion, check whether the key, root, or chord function was misunderstood.