MIDI Converter — Convert MP3, WAV & MIDI Online
One tool for every direction — turn MP3 or WAV recordings into editable MIDI, or render a MIDI file back into shareable MP3 audio, all in your browser.
- MP3 / WAV → MIDI
- MIDI → MP3
- SoundFont rendering
Click a note to hear it
How it works
Choose your conversion
Pick a direction in the converter: audio to MIDI (transcribe MP3/WAV into notes), MIDI to MP3 (render notes to audio), or MP3 to MIDI with a SoundFont.
Upload and preview
Drop your file. For audio to MIDI, preview the transcription on an interactive piano roll; for MIDI to MP3, hear the SoundFont render — before you download.
Fine-tune and download
Adjust detection or swap the SoundFont, edit notes on the roll, then download MIDI, MP3, or export sheet music as MusicXML/PDF.
Formats & limits
- Input formats
- Audio
- Output
- MIDI
- File limits
- 50 MB · 10 min
- Price
- Free · no sign-up
Choosing the right conversion
- Going from a recording to notes? Use audio to MIDI — it works best on clean, monophonic melodies.
- Have a MIDI file you want to hear as audio? Use MIDI to MP3 and upload a matching SoundFont for a natural sound.
- Want to keep the notes but change the instrument? Transcribe with a SoundFont, then re-render with a different .sf2.
- Every conversion previews in the browser first, so you can check the result before committing to a download.
Frequently asked questions
What can this MIDI converter do?
This page is a hub for every conversion direction the site supports, rather than one narrow tool: it transcribes audio (MP3 or WAV) into editable MIDI notes using AI pitch detection, and separately renders an existing MIDI file back into MP3 audio using a SoundFont instrument sample library, so you can move in whichever direction your source material requires. A third path combines both — transcribe audio into MIDI, then re-render it through a chosen SoundFont to hear the melody played by a different instrument entirely. Beyond audio output, any successful transcription can also be exported as sheet music once you're signed in, giving you notation (MusicXML or PDF) rather than just an audio file or raw MIDI, all from the same starting upload.
Which file formats are supported?
On the input side, this page accepts MP3 and WAV for audio-to-MIDI transcription, and Standard MIDI Files (.mid) for MIDI-to-MP3 rendering — pick the direction that matches what you're starting with, and the interface adjusts accordingly. On the output side, you can download a .mid file after transcription, an MP3 after rendering, or sheet music as MusicXML (for notation software) or PDF (for printing or sharing) once you sign in. For the rendering direction specifically, you can also upload a custom SoundFont in the standard .sf2 format to control exactly which instrument samples are used, rather than relying on the built-in default piano sound — useful if you want a specific timbre for the result.
Is the MIDI converter free?
Yes — converting in either direction, previewing the result in the browser, and downloading the basic output (MIDI or MP3) are all free with no account required at any point. Signing in adds three things on top of that: your conversion history persists so you can find past results later, the full note-editing toolkit becomes available for transcriptions instead of just previewing them, and you unlock exporting sheet music as MusicXML or PDF alongside whatever audio or MIDI file you already downloaded. None of that is required for a one-off conversion — if you just need a quick MIDI transcription or a rendered MP3 with no editing, the free anonymous flow handles both directions on its own.
Do I need to install anything?
No — every conversion direction on this page runs entirely inside your browser, with no software download, browser plugin, or DAW required at any step. Audio-to-MIDI transcription and MIDI-to-MP3 rendering both happen through this same web interface: you upload a file, the conversion runs, and you preview the result before downloading anything, all without leaving the page or installing a separate application. This also means it works identically across operating systems and devices — Windows, macOS, Linux, or a tablet — since none of it depends on locally installed audio software, unlike traditional MIDI editors or DAWs that require a specific platform and a real installation before you can open a single file.