Band Stem Mixer

Frequently asked questions

Short answers to common questions. For step-by-step instructions, see the guide.

Is Band Stem Mixer free?
Yes. It is free, with no sign-up, no account, and no ads.
Is my song uploaded?
No. The song is read, separated, and played only in your browser. Nothing about it is sent anywhere. See the privacy policy.
Which parts does it separate?
Four: vocals, drums, bass, and other. “Other” is everything else — guitars, keys, synths, strings — together. Backing vocals usually come out with the vocals.
Can it separate the guitar and the piano?
No. They both go to “Other”. The model was trained to separate four parts; see why guitar and keys stay together.
Which files can I open?
Any audio format your browser can play: MP3, WAV, M4A (AAC), FLAC, Ogg, and others. Songs up to 12 minutes (8 minutes on phones and tablets).
Can I use songs from Apple Music, Spotify, or YouTube?
No. Music from streaming services is protected and cannot be opened in other apps. Use audio files you have, such as recordings of your band or songs you bought as files.
How long does it take?
On a recent computer, about the length of the song or a few times longer; faster with a browser that supports WebGPU. Phones and tablets take longer. The progress bar shows about how long is left.
Why is there a large download?
The AI model (about 172 MB) runs on your device, so the browser has to download it once. It is kept, so the next time there is no download. On mobile data the app asks first. ⚙ → “Delete the AI model” frees the space.
The page reloaded, or separation stopped partway.
The device ran out of memory. Close other tabs and apps and try again: the app uses a lighter setting next time. If it keeps stopping, separate the song on a computer. See if it stops partway.
Does it work on iPhone?
The mixer and saved MP3 files work, but separating may not: iPhones and iPads can run out of memory while separating, and the page reloads. We recommend separating on a computer and playing the saved MP3 files on the iPhone.
I can still hear a little of the part I muted.
AI separation is an estimate, so traces of a part can remain in the others. It is usually quieter than the rest; turning the other parts up a little helps. See why sounds leak between parts.
Are the separated parts saved?
Not in the app: they are gone when you reload or choose another song. Save the ones you want as MP3 files (192 kbps) with the ↓ buttons or “Save this mix (MP3)”. The mixer settings (faders, mute, master volume) are remembered.
Can I publish the parts or a karaoke version I made?
Only for songs whose rights you have, such as your own band's recordings. Publishing or sharing separated parts of someone else's song usually needs the permission of the rights holders.
Can I use it offline?
After your first separation, the app, the AI model, and the separation engine are kept on your device, so it opens and separates without a connection. You can also add it to your home screen.