Chord Progression Generator

Introduction: turn random chords into real songs

This chord progression generator is designed to give you instant harmonic ideas in any key. By choosing a key, scale type, and number of chords, you can quickly create progressions for songwriting, practicing an instrument, or experimenting with new styles. Instead of staring at a blank DAW session or guitar, you get a concrete sequence of chords to play with.

The tool focuses on diatonic harmony: chords that naturally belong to your chosen key and scale (major or minor). This keeps progressions musical and coherent, while still leaving room for you to add your own twists, such as borrowed chords, modulations, or advanced voicings.

How the chord generator works

For each key and scale type, Western music theory defines a set of seven diatonic scale degrees. Each degree can be turned into a triad (a three-note chord). For example, in C major the notes are C–D–E–F–G–A–B, and the diatonic triads are:

• I – C major
• ii – D minor
• iii – E minor
• IV – F major
• V – G major
• vi – A minor
• vii° – B diminished

When you select a key and scale type, the generator builds the corresponding list of diatonic chords behind the scenes. Then it randomly picks chords from that list until it reaches the number of chords you requested.

Basic selection formula

Although this is more conceptual than numerical, the selection process can be represented with a simple function. Each chord in the progression is one random choice from the seven scale degrees:

Here:

• Sd is the list of seven diatonic scale-degree chords in your chosen key and scale.
• rand(1, 7) is a random integer between 1 and 7.
• Chord(i) is the i‑th chord in the progression.

The process repeats until the tool has created a progression with the requested length. Because the chords are always drawn from the diatonic set, your progression will naturally fit the selected key.

Diatonic chords and Roman numeral notation

To understand the output, it helps to think in Roman numerals as well as absolute chord names. Roman numerals show the function of each chord within the key, which makes it easy to transpose progressions into other keys.

In a major key, the typical pattern of triads is:

• I – major
• ii – minor
• iii – minor
• IV – major
• V – major
• vi – minor
• vii° – diminished

In a natural minor key, a common pattern is:

• i – minor
• ii° – diminished
• III – major
• iv – minor
• v – minor (often V major in harmonic minor contexts)
• VI – major
• VII – major

When you see a generated progression like “C – Am – F – G”, you can think of it as I – vi – IV – V in C major. The same pattern in G major would be “G – Em – C – D”.

Interpreting the results

Once you click Generate, you will see a list of chord names based on your chosen key and scale. Here are some ways to interpret and use the output:

• Identify the function: Try translating each chord to Roman numerals, so you understand which chords feel like “home” (I or i), which push forward (V, vii°), and which feel like contrasts (ii, IV, VI, etc.).
• Group chords into sections: Longer progressions can be split into four-chord cells that might become verses, choruses, or pre-choruses.
• Adjust rhythm and repetition: The generator provides chord order, but you decide how many beats or bars each chord lasts, and which chords repeat.
• Adapt to your instrument: Guitarists might choose open chords or barre shapes; pianists can experiment with inversions and broken chords; producers can program the chords as MIDI clips.

Worked example: building a song idea

Imagine you choose:

• Key: C
• Scale type: Major
• Number of chords: 4

The generator might output the progression:

C – Am – F – G

In Roman numerals, this is I – vi – IV – V. Here is one way to turn it into a song idea:

1. Pick a tempo and groove. For a pop feel, try around 100–120 BPM with a straight 4/4 beat.
2. Assign chord lengths. Let each chord last one bar: C (1 bar), Am (1 bar), F (1 bar), G (1 bar), then repeat.
3. Create a simple melody. Improvise a vocal melody or synth line that uses mostly notes from the C major scale (C, D, E, F, G, A, B), making sure to land on strong chord tones (like C on the C chord, A on the Am chord, etc.).
4. Add variation. For a second section, you might use the same chords but change the order, for example: Am – F – C – G (vi – IV – I – V) to give the chorus a different shape.
5. Refine harmony. Once the core idea works, try adding sevenths (Cmaj7, Am7, Fmaj7, G7) or using inversions to smooth the bass line.

In a minor key, the mood shifts. Suppose you choose A minor with 4 chords and get:

Am – F – C – G

This is i – VI – III – VII in A natural minor. Played slowly with a gentle rhythm, it can sound reflective or melancholic. With a faster tempo and brighter sound design, it can work as an uplifting EDM or pop progression.

Using the generator for different genres

The same tool can serve very different musical contexts, depending on how you interpret the chords:

• Pop and rock: Favor major keys and straightforward progressions like I–V–vi–IV or vi–IV–I–V. Strum full chords on guitar or play block chords on piano.
• Electronic and EDM: Use the chords as MIDI clips, experiment with syncopated rhythms, sidechain compression, and layered synths. Often, only two to four chords repeat throughout the track.
• Lo‑fi and hip‑hop: Try minor keys and slower tempos. Use extended chords and voicings with added 7ths and 9ths, and sample or loop short chord sequences.
• Film and game music: Generate progressions in both major and minor keys, then orchestrate them with strings, pads, and subtle melodic motifs.

Comparison: major vs. minor progressions

Major and minor keys often evoke different emotions, even when the chord patterns are structurally similar. The table below compares typical characteristics and example progressions.

Practical workflows with the tool

Writing a verse and chorus

1. Generate a 4‑chord progression in a major key for your chorus. Aim for something strong and memorable.
2. Generate another 4‑chord progression in the same key. Use it as a starting point for your verse. You can tweak one or two chords so the verse feels more subtle or spacious.
3. Ensure both sections share enough chords (for example, at least I and V) so the song feels cohesive.

Practicing on guitar or piano

1. Choose a key and scale type that matches what you are currently studying.
2. Generate a progression and practice changing between the chords smoothly, focusing on clean transitions and timing.
3. Once you are comfortable, generate a new progression and repeat. This keeps your practice varied and realistic.

Limitations and assumptions

The generator is intentionally simple and makes a few key assumptions:

• Diatonic focus: It selects only from chords that belong to the chosen key and scale (major or minor). Non‑diatonic chords such as borrowed chords, secondary dominants, and modulations are not automatically included.
• Triads by default: Output chords are presented as basic triads (e.g., C, Am, F, G). How you extend them (sevenths, ninths, sus chords, etc.) is up to you.
• No voice‑leading rules: The generator does not enforce classical harmony or jazz voice‑leading constraints. Some sequences will sound smoother than others; feel free to discard or edit any output that does not match your taste.
• Style‑agnostic: While example workflows mention specific genres, the tool does not produce genre‑locked patterns. The style comes from your rhythm, sound choices, and arrangement.

These constraints are not drawbacks so much as a reminder that the tool is a starting point. For richer harmony, you can manually add chord substitutions, borrowed chords from parallel keys, or modulate to new tonal centers once you have a basic progression in place.

Tips for extending generated progressions

• Add secondary dominants: Insert chords like V/V (the dominant of the dominant) to create stronger motion toward important chords.
• Use modal interchange: Borrow chords from the parallel minor or major (for example, use iv from the parallel minor in a major key progression) to change the color without leaving the key entirely.
• Experiment with inversions: Put different chord tones in the bass to smooth out jumps and create more interesting bass lines.
• Layer rhythmic variation: Keep the chord order but change the rhythm drastically between sections to maintain interest while preserving harmonic coherence.

Next steps

Use the generator as a quick way to break creative blocks: generate a few progressions, pick one that resonates, and then shape it into something personal through melody, rhythm, and arrangement. Over time, you will also deepen your understanding of keys, scales, and chord functions by seeing how different progressions feel and sound when you play them on your instrument or in your DAW.