Best free stem splitters what the free tier really gives you

The honest split is between "open a tab" and "install something", and it decides most of it:

• One song, right now — StemGrab. Seven stems, six seconds, nothing to install or sign up for.
• The absolute best possible separation, and you have time — UVR on your own machine. Being able to pick the model, chain two of them and tune the settings still beats any one-click web tool if you know what you are doing. It is free, and it is the honest answer even though it is not ours.
• You are comfortable with a terminal — a local separator. Same idea, scriptable, good for batches.
• Practising an instrument — Moises, because the stem separation sits next to a practice player, chord detection and a speed changer. We compare it feature by feature on our Moises alternative page, and LALAL.AI on this one.
• A long DJ set or album side — check the file limit first. This is where the free web tiers stop and where our 90-minute ceiling or a local install matter.

Stem separation is expensive to run: it is a neural network chewing through every second of audio on a GPU. Three business models come out of that, and they explain every row in the table.

1. Free minutes, then a subscription. The most common: ten free minutes is enough to prove the quality and not enough to finish a project.
2. Free, but you install it. Local tools move the GPU cost to your own computer. Unlimited, and the quality ceiling is the highest — at the price of a download, a setup and a slower run on a laptop.
3. Free because the hardware is already paid for. Ours: the same GPUs run our other tools, so an extra song costs electricity, not an API bill. Ads around the tool cover the rest.

There is no fourth model where a company rents cloud GPUs and gives away unlimited separation. If you see that promised, look for where the cap actually is.

We opened each tool's own pricing or product page on 6 August 2026 and noted what it publishes about free limits, accounts and file sizes. We did not run one song through all seven and rank the audio quality — separation quality depends heavily on the mix, and one test track would make that ranking look more solid than it is.

What we can say about ours specifically: StemGrab runs a voice-focused model for the vocal split, measured 2.4 dB cleaner than the model it replaced on our own clips through the live service, and a three-minute song takes about six seconds. That is our own measurement on our own tool, and you should weigh it accordingly.