Chord Progression Generator

Start with four chords. Keep the ones you love, change the rest, and hear where the loop takes you.

Free to generate, edit, play, and download MIDI, MP3, WAV, or a PDF chord chart. No signup required.

100
01I

C · E · G

02V

G · B · D

03vi

A · C · E

04IV

F · A · C

16 beats · 9.6 seconds

A simple keyboard tone previews the notes. The MIDI uses the same root-position triads and chord lengths.

Hear this idea as a full song

Take the current chords, key, tempo, and lengths into the AI song generator as a starting prompt, then add your own mood and lyrics.

Keep working on your music

Generate a full MIDI ideaDescribe a melody, instrument, or musical mood.Transpose a recordingMove an existing audio file into another key.Find a tempo by tappingMatch the pace you hear or have in mind.

A chord progression you can make your own

This random chord progression generator starts with familiar patterns in your chosen key. Change one chord at a time, hold a favorite, and build a useful starting point for a song.
How it works

From a blank page to four chords

Step 01

Choose a key and scale

Pick your home note, choose major or natural minor, and set a tempo between 40 and 240 BPM.

Step 02

Shape the progression

Generate a pattern, lock the chords you want to keep, and replace or lengthen any other chord.

Step 03

Listen, then take the MIDI

Loop the progression while you try a melody. Download its MIDI or open the notes directly in the editor, free and without signing in.

Your next musical idea

Small choices that change the whole song

You control the harmony and its rhythm. Every chord card shows the actual notes you will hear and export.
Four in-key chord cards showing C, G, Am and F with their triad notes.

Random chord progressions that stay in key

Start with common four-chord patterns, then explore the seven triads in your major or natural minor scale. The generator follows musical rules without asking for an AI prompt.
The first C chord stays locked while the other three chord slots change.

Lock a chord and keep exploring

Keep a strong opening or a favorite ending. Regenerate the remaining slots without losing the chord lengths you have chosen.
Each chord has an independent duration selected from one, two, four or eight beats.

Change the pace of each chord

Give each chord one, two, four, or eight beats. A short passing chord and a long final chord can change the feel of the same sequence.
Twelve MIDI note blocks form the C, G, Am and F triads with matching shared pitches.

Editable MIDI, ready for another instrument

Download the exact notes, durations, and tempo shown in the tool. Open the MIDI in Lacuna's editor to move notes or take it into your own music software.
Who it's for

A starting point for the way you write

Use a short harmonic loop to try an idea before committing to a full arrangement.

A songwriter explores a melody at a keyboard in a naturally lit home studio.
01

Songwriters

Loop four chords while trying a topline or a new verse.

A beat maker works with a MIDI keyboard and a music arrangement on a studio monitor.
02

Beat makers

Export a MIDI foundation and assign your own synth or sampled instrument.

An adult guitarist practices chord voicings beside a laptop in a bright living room.
03

Guitarists and keyboard players

Read the chord names, then try your own voicings on an instrument.

An adult music learner compares chords at a digital piano with notes and a laptop.
04

Music learners

Compare major and minor and hear how changing one scale degree affects a loop.

FAQ

Chord progression generator questions

Choose a key, major or natural minor, and a tempo. The tool selects a four-chord pattern using triads from that scale. You can choose another in-key chord in each slot, randomize a single unlocked chord, or regenerate the progression.

Yes. Lock that chord before selecting Generate progression. Locked slots keep their chords and every slot keeps its length. If all four are locked, unlock at least one to generate again.

Every slot keeps its position in the scale and its duration. Changing key transposes all the chords. Changing between major and natural minor adapts their roots and qualities to that scale. Locks apply to random generation, so locked chords also follow a key or scale change.

Yes. The preview and MIDI use the same note pitches, tempo, and chord durations. The preview is a simple synthesized keyboard tone; your music software will use the instrument you select. The file contains root-position triads rather than guitar fingerings or a full arrangement.

Choose Open in MIDI editor to load a copy into Lacuna's existing editor, or download the .mid file for another editor or DAW. Edits in the MIDI editor do not change the generator's four chord cards.

The first version uses the seven diatonic triads in a major or natural minor scale: major, minor, and diminished chords. It does not add borrowed chords, seventh chords, or the raised leading tone of harmonic minor.

Yes. Generate progressions, edit the chords, listen, and download MIDI for free without signing in. The embedded MIDI editor is also available without an account.

Yes. Select Use these chords as song inspiration to bring the current chord names, key, tempo, and chord lengths into Lacuna's AI song generator. Review the starting prompt, add a mood or lyrics, and develop a new song from the idea.

Take your chord idea into a song

Give Lacuna's AI song generator a musical direction and develop it with melody, lyrics, and a full arrangement.