Runs in your browser
Isolate the bassline.
Right in your browser.
Input
or click to choose
MP3, WAV, M4A, AAC, FLAC, OGG, Opus, AIFF and more — plus the audio of MP4, MOV, AVI, WebM, MKV and other video
Six ways to split a track
- FastFastest. Works on phones tooVocals + backing
- 4stem FastFour parts, still light — works on phonesVocals, drums, bass, other
- StandardPick this if unsure — quality without the waitVocals + backing
- 4stemSplit into band partsVocals, drums, bass, other
- 6stemDown to guitar and piano6 parts
- High QualityBest possible — and it takes a whileVocals + backing
Drop in a track and you pick from these. Estimated run times appear then, along with a reason for anything this device does not have the memory to run.
Result
About this process
Free in your browser · instant
Bass extraction isolates the bassline — for transcribing the notes, building a minus-one to practise against, or replacing the low end in a remix.
Bass lives almost entirely in the low frequencies, so the split stands or falls on separating it from the kick drum. The two overlap, and a kick transient can carry through into the bass part. For following the notes this rarely matters, and the extracted bass transcribes cleanly.
Basslines are usually hard to transcribe because they are not really audible. Phone and laptop speakers reproduce almost nothing of the fundamental — roughly 40 to 80 Hz — so inside a mix the bass registers only as a vague weight carried by other instruments harmonics. Isolated, that confusion is gone, and the same speaker becomes enough to follow the movement.
When it is still hard to hear, take the extracted bass to the key and tempo tool and raise the key. It reaches +6 semitones, which is enough to move the line into a range small speakers actually produce. The intervals between notes do not change, so the shape of the part reads the same; subtract the semitones you added when you name the notes.
Highlights
- Bass on its own track
- The 4stem and 6stem models export bass independently of the rest of the mix.
- Buried low end, audible
- Separated from the kick and the rest, the pitch is followable even on laptop or phone speakers.
- Bassless practice track
- Mute the bass, export the mix, and you have a track to play your own part over.
- No upload
- Everything happens inside your browser.
When to use it
- Transcribing a bassline by ear
- Playing along to a mix with the bass removed
- Working out the chord progression from the root notes
- Sampling the low end of a track
Three simple steps
Choose a file
Drag & drop an MP3, WAV, M4A, FLAC or video, or click to select.
Pick a model and start
Bass needs 4stem or better. 6stem returns the same bass part. On a phone, 4stem Fast is the one that runs.
Adjust and export
Preview and adjust each part, then download what you need as WAV.
Bass extractor — frequently asked questions
- Which model isolates the bass?
- 4stem splits into vocals, drums, bass and other, and lets you save the bass track as WAV. Use 6stem if you want guitar and piano on their own tracks too.
- Is the extracted bass in tune with the original?
- Yes — the separated audio is exported as-is, so pitch and timing match the original performance. Where the bass overlaps the kick in frequency you may hear some bleed; 6stem is worth trying in that case.
- Does it work on synth bass and upright bass?
- Both, yes. An upright decays differently from an electric bass but occupies the same role in the low end, so it separates. Synth bass is the less certain one: patches that extend broadband energy well above the fundamental sometimes get filed under other rather than bass.
- The bass drops out in places.
- Either the part rests there, or the kick coincided and the model assigned that moment to the drums. You can tell which by playing the drum track alongside: if the gaps line up with the kicks, it is the separation rather than the arrangement. Re-running on 6stem can change it.
- How do I make the bassless version?
- After separating, mute the bass in the mixer and press "Save this mix". You get the song with a bass-shaped hole in it to play over. One separation gives you both the isolated bass and the mix without it.
- Is it really free? Do I need to sign up?
- It’s completely free with no account needed. Just open the page and pick a file.
- Is the song I choose sent anywhere?
- No. All separation happens entirely inside your browser.
- Which file formats are supported?
- MP3, WAV, M4A, AAC, FLAC and OGG, plus the audio track of video files.