No. It makes the decisions that surround writing — key, tempo, form, harmony and one restriction — so that the writing itself is what you spend your time on. Every element can be overruled, and most writers overrule at least one.

Why does the progression fit the key?

Because the key is drawn first and the chords are built from that key's own diatonic chords. Drawing the two independently would produce briefs where the progression needs transposing before it can be played, which is friction with no benefit.

Are the chord progressions original?

No, deliberately. They are the patterns that recur across a great deal of popular music, because a brief is a starting point and an unfamiliar progression makes it a harder one. Chord progressions are not copyrightable in themselves, and what you write over one is yours.

How is this different from the chord progression generator?

That gives you a progression. This gives you a complete brief — the progression plus the key, tempo, time signature, form and a restriction to write against. If you only need chords, use the other one.

Songwriting Constraint Generator

A songwriting prompt that gives you a mood or a title leaves you with all the actual decisions still to make. This gives you the decisions: a key, a tempo, a time signature, a chord progression that fits the key, a song form, and one restriction to work against. What is left is the part that is actually writing.

Your songwriting brief will appear here.

What this generator does

Produces a brief with six parts that fit together rather than six independent draws. The chord progression is generated in the key that was drawn, using the diatonic chords of that key, so it is playable as given rather than needing transposing. The tempo is drawn within a range that suits the form — a ballad brief does not come out at 170 beats per minute — and the restriction is drawn last, from a bank of limits that apply to whatever else was chosen.

How to use this tool

Press Generate for a complete brief.
Reroll any single element you cannot work with, rather than starting over.
Write to it. The restriction is the part to take seriously.
Give yourself a deadline — an hour is enough for a first draft of something short.

Understanding the controls

Key range: Practical keys are the ones real songs are written in, which for guitar and piano is a fairly short list. All keys includes the awkward ones, which is useful precisely because you would never choose them.
Form: Verse-chorus, verse-chorus-bridge, AABA and twelve-bar are the forms most popular songs use. Choosing one before you write is what stops a song becoming four verses and no shape.
Restriction: One limit to write against — no more than three chords, a single-syllable title, no rhymes, the whole lyric in the second person. This is the part of the brief that produces something you would not otherwise have written.
Reroll individual parts: Any single element can be redrawn without losing the rest. A brief you can partly reject is one you will actually use; an all-or-nothing brief gets regenerated until it is comfortable, which defeats it.

Worked examples

A pop brief: G major, 92 bpm, 4/4, G–D–Em–C, verse-chorus-bridge. Restriction: the chorus may not contain the title.
A blues brief: E major, 128 bpm, 4/4, twelve-bar. Restriction: no more than five different words in the whole chorus.
An awkward one: D♭ major, 68 bpm, 6/8, AABA. Restriction: write it in the second person throughout.

Common use cases

Breaking a writing block by removing the choices that cause it
Songwriting challenges where everybody writes to the same brief
Getting out of the two keys and one tempo you always write in
A songwriting class needing a different brief per student
Practising writing to a spec, which is what commissioned work actually is

How this generator works

The key is drawn first, because everything else depends on it. The chord progression is then built from that key's diatonic chords using one of the progressions that recur across a great deal of popular music — I-V-vi-IV and its relatives — so it is idiomatic rather than arbitrary. The form is drawn independently, and the tempo is drawn from a range associated with that form rather than from the whole scale, which is why a twelve-bar brief tends to come out faster than a ballad. The restriction comes last and is drawn from a bank deliberately weighted towards limits on words and structure rather than on harmony, because the harmony has already been decided for you.

Randomness and fairness

The key is drawn first and the progression is then derived from it, so those two are related rather than independent. The form, the tempo and the restriction are drawn separately, with tempo conditioned on the form. Everything comes from the browser's cryptographic random number generator, and a seed makes a whole brief reproducible so a class can write to the same one. A seeded brief is generated deterministically and is not cryptographically secure; anybody with the seed gets the identical brief, which is the entire point of setting one.

For how randomness is produced across the whole site, see how Generate Random works.

Assumptions this tool makes

The song is in a Western popular idiom, which is what the forms and progressions come from.
The progression is given in the drawn key and is meant to be played as written rather than transposed.

Limitations and good to know

It writes nothing. No lyrics, no melody, no arrangement — the brief is a set of decisions, and every one of them can be overruled.
The chord progressions are common Western popular-music patterns. They are idiomatic rather than original, which is the point of a starting brief and a limitation if you were hoping for novelty.
Tempo ranges by form are conventions rather than rules. Plenty of well-known songs sit well outside the range their form usually implies.
It knows nothing about your voice, your range, or what you have already written.
A brief cannot make a song good. It can stop you making the same decisions you always make, which is a different and smaller claim.

Common mistakes

Rerolling until the brief is comfortable: The uncomfortable brief is the one that produces something new. Reroll one element you genuinely cannot work with and keep the rest, which is why the parts reroll individually.
Treating the restriction as optional: It is the only part of the brief that changes how you write rather than what you write about. Drop it and you have a key and a tempo, which you already had.
Starting with the lyric: The brief hands you harmony, tempo and form. Playing the progression at the tempo for a few minutes before writing a word uses what you have been given rather than ignoring it.

Practical tips

Set a deadline with the brief. An hour produces a finished sketch; an open-ended brief produces an unfinished one.
Write the worst possible version first and fix it. A brief plus perfectionism produces nothing at all.
Keep the briefs you did not use. A brief that felt wrong in January is often exactly right in June.

Troubleshooting

The key is unplayable on my instrument: Reroll just the key, or transpose the progression — it is given in scale degrees as well as chord names for exactly that reason.
The restriction contradicts the form: Occasionally they pull against each other, and working out how to satisfy both is usually the most interesting part. If it is genuinely impossible, reroll the restriction.

Privacy and your data

Nothing is entered and nothing is stored. Briefs are generated in your browser, no brief is uploaded or written into the page address, and analytics records only that the tool was used along with the form chosen — never a brief.

Frequently asked questions

Does it write songs?: No. It makes the decisions that surround writing — key, tempo, form, harmony and one restriction — so that the writing itself is what you spend your time on. Every element can be overruled, and most writers overrule at least one.
Why does the progression fit the key?: Because the key is drawn first and the chords are built from that key's own diatonic chords. Drawing the two independently would produce briefs where the progression needs transposing before it can be played, which is friction with no benefit.
Are the chord progressions original?: No, deliberately. They are the patterns that recur across a great deal of popular music, because a brief is a starting point and an unfamiliar progression makes it a harder one. Chord progressions are not copyrightable in themselves, and what you write over one is yours.
How is this different from the chord progression generator?: That gives you a progression. This gives you a complete brief — the progression plus the key, tempo, time signature, form and a restriction to write against. If you only need chords, use the other one.