ABOUT

An audio to MIDI converter that runs on your device

Most online converters ask you to upload a recording, wait in a queue, and then download a file from someone else's server. This one does the whole job inside your browser tab.

How the conversion works

The page decodes your audio with the browser's own Web Audio API, then walks through the recording in short overlapping frames. For each frame it looks for the strongest repeating pattern in the waveform, turns that pattern into a pitch, and converts the pitch to a MIDI note number. Consecutive frames that agree are merged into a single note. The finished notes are written into a standard .mid file that you download directly.

None of this requires a server. There is no queue, no account, and no file transfer.

What it handles well

• A solo vocal or hummed melody
• A single piano or guitar line
• An isolated stem pulled out of a larger mix
• Short, clean recordings without heavy effects

Where it struggles

• Full mixes with drums, bass and several instruments at once
• Dense chords where no single pitch dominates
• Noisy or heavily compressed recordings
• Material with lots of vibrato, slides or pitch bending

Think of the download as an editable starting point rather than a finished transcription. Import it into a DAW and clean it up there.

Supported formats

MP3, WAV, M4A, OGG, FLAC and WMA. Exactly one file at a time. The output is a standard MIDI file with a tempo of 120 BPM and a resolution of 480 ticks per beat.

Why it is free

There is nothing to meter. Because the conversion happens on your own hardware, serving the page costs almost nothing, and there are no ads and no trackers on it.