Audio to MIDI Converter

The clearest results usually come from recordings where one pitched instrument or one melodic line is easy to hear. Solo piano, isolated guitar, bass, humming, whistle, synth leads, and instrument stems are good starting points because the model can separate their fundamentals and attacks more reliably. Polyphonic piano can also work well, although dense chords and pedal resonance may introduce extra harmonic energy that sometimes looks like additional notes.

A mastered song is harder. Drums create strong transients without stable pitch, vocals and guitars overlap, bass can mask low notes, reverb smears note endings, and compression changes the shape of attacks. The converter can still produce useful material, but a full mix should be treated as a draft transcription rather than a finished score. If you have access to stems, upload the instrument stem you actually want to edit instead of the complete mix. Removing unnecessary layers before conversion is often more effective than trying to fix hundreds of unwanted MIDI notes afterward.

Raw transcription models tend to create a few classes of editing problems: tiny fragments, same-pitch overlaps, model latency, and repeated notes that are accidentally fused into one long note. The default cleanup removes extremely short notes, merges overlapping notes of the same pitch, shifts timing to compensate for measured model latency, and can inspect the original audio for a clear second attack inside a long note. The repeated-attack detector is intentionally conservative because splitting every energy change would create the very fragments the cleanup is meant to remove.

Tempo and quantization are separate choices. Auto tempo estimates a practical BPM from detected note onsets, but a human performance may speed up and slow down across a phrase. Preserve Performance leaves those differences in place. Quantize can instead snap starts to an 1/8, 1/16, or 1/32 grid, and you can choose whether note endings should be snapped too. For expressive piano or rubato, preserving timing is often safer. For loops, electronic parts, or material that will be heavily edited in a DAW, a moderate grid can make the output faster to work with.

The downloaded MIDI is a standard .mid file, so the notes are no longer locked inside the original recording. You can import it into Ableton Live, FL Studio, Logic Pro, Cubase, Reaper, GarageBand, Bitwig, Studio One, or a notation application and change pitch, note length, velocity, tempo, instrument, key, arrangement, and track structure. That makes audio-to-MIDI useful for reconstructing a melody, studying harmony, replacing a sound with a synth, creating notation, or using an existing performance as the starting point for a new arrangement.

Automatic transcription does not know your creative intent. A chord tone and a melody note may appear on the same track, left- and right-hand piano parts may not be separated, and quiet notes can be missed when louder material covers them. Editing is therefore a normal part of the workflow rather than evidence that the conversion failed. The goal is to replace the slow task of entering every note manually with a useful first pass that already captures much of the pitch and timing structure.

The transcription runs in the browser. When you start a conversion, the page loads the model code it needs, decodes the selected audio locally, performs note estimation on your device, builds the MIDI, and creates a browser download. The recording itself is not sent to our application server for transcription. This is useful for unfinished songs, client work, rehearsal takes, private demos, classroom recordings, and other material you may not want to hand to a remote file-conversion service.

Local processing also has a practical trade-off: your computer or phone provides the CPU, memory, and browser features. That is why the current free version uses a five-minute and 100 MB limit. A desktop Chromium or Firefox browser is usually the most reliable environment for longer or more complex files. If a format does not decode on your device, converting it to WAV or MP3 first is a simple compatibility fallback. The limit is about keeping the browser workflow predictable, not about hiding the download behind a paid plan.