Splitting a track into vocal and instrumental is the easy half. Every free tool does it, and they all use roughly the same open model. The half nobody does is handing the result back ready to play.
Run a song through a typical vocal remover and you get a bare WAV: no key, no tempo, no beatgrid, no tags. Drag it into Serato and you wait for an analysis pass, then you check the grid by hand, then you type the key into the comments field because the analyser disagreed with what you know the record is. That is the actual cost of a "free" separation, and you pay it on every single file.
All four travel inside the file itself. Nothing to re-enter, nothing to re-analyse.
Standard key analysers confuse parallel major and minor on roughly a fifth of electronic records — F minor comes back as F major. That single error class is why so many DJs stop trusting automatic key detection and go back to typing it in themselves. Tuning specifically for electronic music cuts those parallel-mode errors to under 2%, measured across 2,579 tracks. The full method and numbers are on the accuracy page.
Each claim stands on its own evidence. If two independent tempo estimators disagree about a record, you get the audio with no tempo rather than a guess. If the detected beats do not land cleanly on that tempo, you get the tempo but no grid. A labelled file with no grid is useful; a wrong grid costs you a rebuild mid-set.
Drop a track and hear the first 30 seconds free. No account, no card.
Open the toolThe first 30 seconds of any track are free, every time, with no account. Beyond that it is €0.10 per minute of audio, bought in credit packs. There is no subscription.
Lossless AIFF plus MP3 320. Separation uses htdemucs_ft, the same open model most of the category runs on, so quality is comparable to the well-known tools.
No tool gives a perfectly clean vocal on every record, and any that claims to is overselling. Dense, heavily-processed mixes leave artefacts. Try the free 30 seconds on the track you actually care about before buying credits.
The file you download already carries its key, its tempo and a Serato beatgrid. Every other tool hands you a bare, untagged file that your DJ software then has to analyse from scratch.