Nothing is uploaded
There is no upload endpoint in this page at all. Your unreleased mix, your client’s stems and your voice memo are read by the tab and stay there. Closing it deletes everything.
Free tool · Nothing uploaded
Take the vocal out of a song without handing the song to anyone
Most vocal removers upload your file, put it in a queue and email you a link. This one downloads the separation model to your browser instead and runs it there, so the audio never leaves the tab. You get an instrumental and an acapella, both as WAV.
Runs in your browser · No account · Up to 10 minutes per track
The separator
One file in, two stems out
The first run downloads about 64 MB of model, which your browser then caches. Separation is real work — expect it to take a few minutes on a normal laptop, and longer than the song itself unless your browser supports WebGPU.
What is different here
The file stays on your machine
That is not a privacy slogan bolted onto the same architecture as everyone else — it is a different architecture, and it has consequences worth knowing before you choose a tool.
The stems sum back to the original
The model estimates the instrumental and the vocal is what is left over, so adding the two back together reconstructs your file exactly. That is what makes the instrumental usable as a karaoke bed rather than an approximation of one.
Your machine does the work
Which is the trade: no queue and no cost, but no server farm either. WebGPU browsers finish in well under the length of the song; without it you are on single-threaded WebAssembly and it takes noticeably longer.
How it works
Spectrograms, not magic
Worth knowing what the tool is doing, partly because it explains the wait and partly because it tells you when the result will be good.
- 01
Your file is decoded and resampled
To 44.1 kHz stereo, because that is what the model was trained on. A mono file is played through both sides; anything the browser can decode is accepted.
- 02
The audio becomes a picture of itself
Six-second chunks are turned into spectrograms — a 6144-point transform every 1024 samples, which is what the model expects to be handed.
- 03
The model estimates the instrumental
Chunk by chunk, with the edges cross-faded so you do not hear a seam every six seconds. This is the part that takes the time.
- 04
The vocal is what is left
Subtracting the estimated instrumental from your original gives the vocal, and guarantees the two halves add back up to what you started with.
Two honest limits. Separation is imperfect on dense mixes — heavy reverb, doubled vocals and loud cymbals are where you will hear artefacts, in both stems. And a long track holds the mixture and both stems in memory at once, which is why the ceiling is 10 minutes rather than an album side.
Credit
The model is not ours
Separation uses UVR-MDX-NET-Inst_HQ_1, trained and released by the Ultimate Vocal Remover project under the MIT licence, which asks that developers who use its models credit it. The architecture is MDX-Net, from KUIELab. We built the browser side; they built the part that does the actual work.
After the split
A stem is the start of something, not the end
An instrumental is a bed to talk over and an acapella is a hook to build around. PrismPoster is where the rest of it gets made: music, video and images in one studio, and a timeline to cut them together.
- Generate original music instead of borrowing someone else’s bed, and skip the licensing question entirely.
- Cut the stem into a video in the same place, rather than exporting between four tools.
- Start free with 50 credits, no card, and judge it on what comes out.
The separator stays free and local whether or not you ever open an account.
See how the Music Studio worksQuestions
The ones worth answering
Is it really free, with no limit?
Yes. There is no account, no email and no per-track cap, because there is nothing for us to meter — your computer does the work, not our servers. The only limits are technical: 10 minutes per track, and your machine’s memory.
Is my audio uploaded anywhere?
No. The page has no upload path. Your browser downloads the model and runs it locally, which is the opposite arrangement to most vocal removers: they send your file to a server, this sends a model to you. You can watch it in your browser’s network tab — the only sizeable request is the model coming down.
How long does it take?
It depends entirely on your browser. With WebGPU, comfortably less than the length of the track. Without it, separation falls back to single-threaded WebAssembly and takes longer than the song — several minutes for a normal single. The first run also downloads about 64 MB of model, once.
How good is the separation?
Good enough for a karaoke bed, a practice track or a sample, and not good enough to pass as a studio multitrack. Sparse mixes separate cleanly; dense ones leave artefacts — you will hear them most in cymbals, heavy reverb tails and doubled vocals. Listen to both stems before you commit to one.
Which files can I use?
Anything your browser can decode, which in practice means MP3, WAV, M4A/AAC, FLAC and OGG. Both stems come back as 44100 Hz stereo WAV, which is lossless and drops straight into any editor.
Can I use the stems commercially?
That depends on the song, not on this tool. Separating a recording does not give you any rights to it — an instrumental made from a track you do not own is still that track. For your own recordings, do as you like. If you need music you can actually license, generating it is the cleaner answer.
Explore more
BPM tapper
Find the tempo of the stem you just pulled out.
AI lyric generator
Write the words for the track you are building around it.
How the Music Studio works
Generating a bed instead of borrowing one.
Subtitle converter
SRT and WebVTT, converted in the browser like this one.
Everything in PrismPoster
Image, video, music, editing and export in one place.
Pricing
What the free plan includes and what the paid plans cost.
Free to start
You have the stem.Now make the rest.
PrismPoster generates music, video and images and cuts them together in one place. Start free with 50 credits and no card.