🎵 Chord Progression Generator
Enter a major key and a progression in Roman numerals — like I-V-vi-IV — and get the real diatonic chords to play, transposed to whatever key you choose.
🎵 Generate Your Chords
What is a Chord Progression Generator?
It translates the language of Roman-numeral progressions into the actual chords for your key. Enter a key and a sequence like ii-V-I, and it builds the major scale, maps each numeral to a scale degree, and names the chord with the right major, minor, or diminished quality.
Because numerals are relative, the same progression instantly transposes to any key — write it once and play it everywhere. It's a fast way to explore songwriting ideas, understand the songs you already know, and connect theory to the fretboard.
❓ Frequently Asked Questions
How does the chord progression generator work?
It builds the major scale of the key you enter using the standard step pattern, then reads your Roman numerals and maps each to a scale degree. The case of the numeral sets the quality — uppercase is major, lowercase is minor — and the vii chord (or any numeral with a ° or 'dim' suffix) comes out diminished. The result is the actual chord names to play.
How do I write a progression?
Use Roman numerals I through vii joined by dashes, for example I-V-vi-IV or ii-V-I. Uppercase numerals give major chords, lowercase give minor, and you can add ° or 'dim' to force a diminished chord. The numerals are relative to the key, so the same progression transposes to any key you enter.
What are diatonic chords?
Diatonic chords are the chords built only from the notes of a key's major scale. In any major key the pattern of qualities is fixed: I, IV, and V are major; ii, iii, and vi are minor; and vii is diminished. That's why I-V-vi-IV sounds like a pop progression in every key — the relationships stay the same.
Why does it use sharp spelling?
The generator spells notes with sharps for a single consistent naming scheme, so it's built for sharp-compatible major keys. In formal notation some keys are spelled with flats — the chord that sounds the same might be written differently — but sharp spelling keeps the output clear for playing on the guitar.