Chord Progression Builder - Online Music Theory Tool
Select a key and build chord progressions (I-IV-V, etc.). Hear them played with simple piano sounds. Great for songwriting inspiration. Local audio synthesis.
UD5 Toolkit
Instantly generate inspiring chord progressions for your next song. Pick a key, choose a style, and let creativity flow.
Your saved chord progressions will appear here. Click a progression to load it.
A chord progression is a sequence of musical chords played one after another. It forms the harmonic foundation of a song, supporting the melody and establishing the emotional tone. Popular progressions like I–V–vi–IV appear in countless hit songs across genres.
Our tool uses music theory algorithms to generate musically coherent chord progressions within your chosen key and mode. It draws from common progression patterns used in pop, jazz, folk, classical, cinematic, and experimental music. You can customize the key, mode, style, number of chords, BPM, and optionally include seventh chords for richer harmonies.
Roman numerals represent chords based on their position within a scale. Uppercase (I, IV, V) indicates major chords; lowercase (ii, iii, vi) indicates minor chords; and vii° indicates a diminished chord. This system is key-agnostic, making it easy to transpose progressions to any key. For example, I–V–vi–IV in C major is C–G–Am–F.
Seventh chords add a fourth note (the seventh degree) to a triad, creating richer, more colorful harmonies. They're essential in jazz (maj7, m7, 7, m7b5), R&B, and modern pop. Enable the "7th Chords" toggle to incorporate them into your progressions. Dominant seventh chords (like G7) naturally resolve to the tonic, adding satisfying tension and release.
Common keys for popular music include C major, G major, D major, and A major (or their relative minors: Am, Em, Bm, F#m). C major and A minor use only white keys on a piano, making them beginner-friendly. Vocalists often prefer keys like G or F that suit their vocal range. Experiment with different keys to find what resonates with your melody.
Major mode generally sounds happy, bright, and uplifting. Minor mode tends to sound sad, melancholic, or dramatic. However, chord progressions can mix moods—a major progression can feel bittersweet, and a minor progression can sound powerful. Try both modes to explore different emotional landscapes for your music.
Start by looping the progression at a comfortable BPM. Hum or sing a melody over it, letting the chords guide your vocal line. Experiment with different rhythms, strumming patterns, or arpeggios. Many songwriters build verses around one progression and switch to a different one for the chorus. The progression can also inspire lyrics by setting an emotional foundation.
Yes! Click the Save (bookmark) button after generating a progression to store it in your browser's local storage. Your saved progressions will appear in the "Saved Progressions" section and persist even after closing the page. Click any saved progression to reload it instantly.
Select a key and build chord progressions (I-IV-V, etc.). Hear them played with simple piano sounds. Great for songwriting inspiration. Local audio synthesis.
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