Written by Emily Sanders | Last updated: June 2026
About the Tool
What does the Chord Progression Maker do? The tool generates chord progressions based on your selected root note, key, and progression style using documented diatonic harmony rules. It applies functional harmony logic — tonic, subdominant, and dominant chord functions — to produce sequences that are theoretically grounded in the key you select. Each chord in the output is labelled with its name, quality, Roman numeral, and functional role. The full technical documentation of the generation pipeline is on the How It Works page.
Does this tool use audio, microphone, or file upload? No — none of these. The Chord Progression Maker is a pure music theory calculation tool. It requires no microphone permission, accepts no audio file uploads, and makes no server requests for tool output. Everything runs locally in your browser using JavaScript. No data of any kind is transmitted as part of using this tool. See the Data Security page for the full explanation.
What keys and modes does the tool support? The tool supports all 12 root notes (C, C#/D♭, D, D#/E♭, E, F, F#/G♭, G, G#/A♭, A, A#/B♭, B) in both major and natural minor modes. This covers all 24 major and natural minor keys. Harmonic minor and melodic minor variants are applied automatically where the dominant chord is involved in a minor key progression.
Does the tool generate seventh chords? Yes, where the selected progression style includes seventh chords. The tool calculates diatonic seventh chord qualities using the same stacking-thirds logic as triads — correctly distinguishing between major seventh (Imaj7), minor seventh (ii7, iii7, vi7), dominant seventh (V7), and half-diminished seventh (viiø7) across all keys.
Understanding Your Results
What does the Roman numeral label mean? Roman numerals name each chord by its scale degree position and quality within the key. Uppercase Roman numerals (I, IV, V) indicate major chords; lowercase (ii, iii, vi) indicate minor chords; a degree symbol (°) indicates diminished. The Roman numeral system allows the same functional relationships to be described across all keys — a I–IV–V–I progression works the same way in C major and in F# major, even though the specific chords are different.
What does “tonic,” “subdominant,” and “dominant” mean next to each chord? These labels describe the functional role of each chord in the progression. Tonic chords (I, iii, vi in major) provide harmonic rest and stability — the “home” feeling. Subdominant chords (II, IV) create movement away from rest and prepare the ear for tension. Dominant chords (V, vii°) create harmonic tension that pulls strongly toward resolution back to the tonic. Understanding these functions tells you why a chord is where it is in the sequence — not just what it is.
The tool generated a progression but it doesn’t sound right to me. Is the tool wrong? Not necessarily — but this is the most important limitation to understand. The tool generates progressions that are correct according to diatonic harmony rules. Whether a progression works in a specific musical context depends on factors the tool cannot assess: genre conventions, voicing, tempo, harmonic rhythm, and the melodic content above the chords. A I–ii–V–I progression is theoretically sound in C major; whether it fits the song you are writing depends entirely on the song. Think of the output as a theoretically grounded starting point, not a finished musical answer.
Why does the same progression pattern produce different chords in different keys? Because the diatonic chord set is unique to each key. In C major, the IV chord is F major. In G major, the IV chord is C major. The Roman numeral (IV) describes the function and scale degree — not the specific chord. This is the entire purpose of the Roman numeral system: to describe harmonic relationships in a way that transfers across keys.
What is the difference between a major I chord and a minor i chord? The I chord (uppercase) in a major key is a major triad. The i chord (lowercase) in a minor key is a minor triad. The tonic of a major key produces a major triad; the tonic of a minor key produces a minor triad. This difference in quality gives major and minor keys their characteristic sounds — major feeling brighter and more stable; minor feeling darker and more tense.
Music Theory Questions
What is functional harmony? Functional harmony is the system that describes how chords relate to a tonal centre and to each other based on their role (function) within a key. Every chord in a key has a primary function — tonic (rest), subdominant (preparation), or dominant (tension) — and functional harmony describes the logic of how progressions move between these states. It is the foundation of tonal music from Baroque to contemporary pop and the theoretical basis for everything the Chord Progression Maker generates.
What is a secondary dominant? A secondary dominant is a chord that functions as a dominant (V) to a chord other than the tonic. For example, in C major, the V of V (D major, written V/V or D7) creates tension that resolves to the G major chord rather than to C. Secondary dominants temporarily tonicise a non-tonic chord — they are the most common type of chord substitution in tonal music and one of the primary tools for adding harmonic interest to a diatonic progression.
What is modal interchange? Modal interchange — also called borrowed chords — involves using a chord from the parallel minor key in a major key progression (or vice versa). In C major, for example, the iv chord (F minor, borrowed from C minor) can replace the diatonic IV (F major) for a darker colour. The bVII chord (B♭ major in C major) and the bVI chord (A♭ major in C major) are common borrowed chords in pop and rock. Modal interchange expands the harmonic vocabulary of a key beyond its strictly diatonic chords.
Why does the tool raise the V chord in minor key progressions? In natural minor, the V chord is a minor triad (v) — it lacks the leading tone that gives the dominant chord its strong pull toward the tonic. Classical and tonal music typically raises the seventh scale degree in minor to create a major V chord (called harmonic minor), restoring the leading tone and the strong dominant-to-tonic resolution. The tool applies this raising automatically in minor key progressions where the dominant function is occupied by the V chord, following standard tonal harmony practice.
Can I use this tool for jazz harmony? The tool generates diatonic progressions based on classical functional harmony. Jazz harmony extends and modifies this system significantly — using extended chords (9ths, 11ths, 13ths), tritone substitutions, chromatic voice leading, and modal approaches that operate outside strict diatonic harmony. The tool is most directly applicable to tonal jazz (ii–V–I progressions, standard form harmony) and less applicable to modal jazz or post-bop styles where diatonic function is de-emphasised.
Accuracy and Limitations
Are the generated progressions always musically correct? They are correct according to diatonic harmony theory. Whether they are musically effective in a specific context is a different question — one that depends on genre, voicing, melodic content, and creative intent. The tool provides a theoretically grounded starting point; musical judgment determines what to do with it.
Does the tool handle enharmonic equivalents? The tool follows standard theoretical enharmonic conventions — F# in the context of G major, G♭ in the context of D♭ major. Where enharmonic ambiguity exists, the tool applies the spelling most consistent with the key’s sharps or flats. If a specific enharmonic context requires different spelling, this should be adjusted manually.
Can the tool generate chord inversions? The tool currently generates root-position chord names. Inversions — where a note other than the root is in the bass — affect voice leading and bass line movement significantly but are not specified in the current output. Inversion choices are a voice leading and arrangement decision that follows from the generated progression.
About This Website
Who runs ChordProgressionMaker.com? ChordProgressionMaker.com is built and maintained by Emily Sanders, music theory educator and harmony researcher. Emily writes all content on the site personally. There are no guest contributors, no sponsored content, and no advertisers. For Emily’s full background and the reasons this site was built, see the Author page.
Is this site free to use? Yes. The Chord Progression Maker and all educational content on ChordProgressionMaker.com are completely free. No registration, no account, and no payment of any kind is required.
How do I report a theory error or ask a question? Email contact@chordprogressionmaker.com with the subject line “Content Correction” for theory errors or “Technical Question” for tool questions. Emily reviews all submissions personally. Response time: 48–72 hours.
Written by Emily Sanders, founder of ChordProgressionMaker.com. Last updated: June 2026.