What you get, and what you do not
| Included | Details |
|---|---|
| Notes with start, length and velocity | Polyphonic: several notes at once, such as chords and piano |
| Piano-roll preview and playback | A plain synth plays the MIDI so you can check it against the original |
| Cleanup controls | Notes fewer to more, shortest note, one note at a time, optional pitch bends |
| Standard MIDI file | One track at 120 BPM; notes keep their real timing in seconds |
It does not give you sheet music, chord names, drum or percussion tracks, or the sound of the original instrument. MIDI is only the notes: you choose the instrument that plays them. For chord names use the chord finder.
How accurate is audio to MIDI?
Honest answer: approximate. Note transcription from audio is hard, and a single clean instrument gives the best result. A solo piano, a guitar line or a vocal melody usually comes out well enough to edit. A full mix with drums, bass, vocals and effects will contain wrong notes, missing notes and notes in the wrong octave.
| Source | Typical result | Tip |
|---|---|---|
| Solo piano or keys | Good: most notes right, some extra or missing | Keep the notes slider near the middle |
| Guitar, one line | Fair to good | Use One note at a time for single-note lines |
| Voice or humming | Fair; vibrato can split notes | Raise the shortest note to 100 ms or more |
| Full song mix | Rough sketch only | Split stems first and convert one stem |
| Drums, noisy or distorted audio | Poor: pitch tracking has nothing to follow | Not a good fit for this tool |
Expect to tidy the result in your DAW. The preview and the sliders are there so you can get close before you leave the page.
Best results: split first, then convert one stem
Transcription models are trained on single instruments, so the cleaner the input, the cleaner the MIDI. Use the stem splitter to pull the instrument you want out of the mix, download that stem, and drop it here.
| You want MIDI of | Split with | Then |
|---|---|---|
| The piano or keys | Piano extractor | Convert the piano stem |
| A guitar riff | Guitar extractor | Convert the guitar stem with One note at a time |
| The bass line | Stem splitter (bass stem) | Convert the bass stem |
| The vocal melody | Vocal remover | Convert the vocal stem with One note at a time |
Why it is private and free
The transcription model is small (under 1 MB) and runs on your device through TensorFlow.js, so there is no server to upload to, no queue, and no free-trial limit on how many files you convert. The model files are loaded only after you drop a file.
The model is Basic Pitch by Spotify, released under the Apache-2.0 licence. TuneSplit hosts a copy of the model files and the licence text with the site.
Phone and computer notes
- Works in current Chrome, Edge, Firefox and Safari. A computer is faster; a six-minute file can take a minute or two on a phone.
- Files longer than 6 minutes are refused with a message so a phone does not run out of memory. Trim first with the audio cutter.
- Keep the tab open and in front while it works: some phones pause background tabs.
- Downloads go to your Files or Downloads folder like any other file.
Frequently asked questions
Is this audio to MIDI converter really free?
Yes. There is no sign-up, no card and no per-file limit. The only limit is length: up to 6 minutes per file, so browsers do not run out of memory.
Is my audio uploaded anywhere?
No. Decoding, transcription, preview and the .mid file are all made in your browser. The only request is for the small model files, which are the same for everyone. You can check the Network tab in developer tools.
How accurate is the MIDI?
Approximate. A single clean instrument such as piano usually comes out well; a full mix gives a rough sketch with wrong and missing notes. Split the stem first for the best result and expect to edit in your DAW.
Can it convert a whole song with drums and vocals?
It will try, but the result is messy because the model follows pitched notes and a mix has many overlapping sources. Split the song into stems and convert the one you want.
Does it export chords or sheet music?
No. It exports notes as a MIDI file. For chord names with timestamps use the chord finder; for sheet music, open the .mid in a notation app.
What does the notes slider do?
It changes how sure the model must be before it keeps a note. Toward fewer gives a cleaner line with some notes missing; toward more keeps faint notes and adds some wrong ones. Changing it is instant and does not re-run the model.
Which model does it use?
Basic Pitch, an open-source note transcription model from Spotify, licensed Apache-2.0. It runs through TensorFlow.js in your browser.
Does it detect the tempo?
The MIDI file is written at 120 BPM with notes placed at their real times, so it lines up with the original audio. Use the BPM finder to get the song's tempo and set it in your DAW.