Choose six dials
Style, mood, theme, tempo, song type and synthesis engine. Lock any of them and the randomiser will respect it.
Generative composer · browser native · offline
Music you can
regenerate.
One tap composes a finished-sounding track — harmony, melody, drums, mix and master. Every song is a pure function of six presets and a 12-character seed, so a link is a recording. No accounts. No server. No samples.
- 11 styles
- 10 moods
- 7 synth engines
- 0 network requests
live specimen
Every note below was generated in your browser a moment ago.
01 — how it works
It composes, not shuffles
An eleven-stage pipeline builds harmony from a Markov grid, voices it with a voice-leading solver, develops a motif across sections and masters the result.
Take it somewhere
WAV, per-track stems, Type-1 MIDI, cover art, or a seed link that reproduces the exact same song on someone else's phone.
02 — inside
Deterministic by construction
The composer contains no Math.random, no Date.now and no
DOM. Same presets plus same seed produces a byte-identical song — asserted over a
hundred runs in the test suite, not just claimed in a README.
compose(presets, seed) → Song
Real synthesis
Subtractive, FM, chiptune pulse, additive, wavetable, Karplus-Strong and noise — plus a drum kit built from oscillators and filtered noise. No audio files ship.
A theory validator, not a dice roll
Every note is checked against the key and the chord sounding under it. Random is sampled through a compatibility table, so it stays musical.
Loudness that holds
An ITU-R BS.1770 implementation runs in the app and in the tests. Exports are normalised to the style's target under a −1 dBTP ceiling.
Offline, honestly
The service worker precaches the whole shell and the app makes no runtime requests — no fonts, no analytics, no CDNs. Install it, switch off the network, keep composing.
caches: musicgen-v2 · fetch: cache-first · CSP: default-src 'self'
03 — the numbers
- 43 KB
- gzipped, whole app
- 330/330
- theory-validator cases pass
- 48
- automated tests
- 5
- export formats
04 — install
It installs like an app and behaves like one.
Open the studio, then use your browser's Install or Add to Home Screen. iOS: Share → Add to Home Screen. From then on it launches offline, with its own icon, and keeps playing when you switch apps.
# or run it locally git clone https://github.com/drsamonline/musicgen cd musicgen/app python3 -m http.server 8080 # → http://localhost:8080