How to Convert Audio to MIDI Online (Free Audio-to-MIDI Converter)
Converting audio to MIDI lets you pull the notes out of a recording so you can edit, re-instrument and rework them inside a DAW. The free browser-based Audio to MIDI converter reads an MP3, WAV, FLAC, M4A or other audio file and writes a MIDI file with the detected pitches and timing. No signup is needed and files up to 500 MB are supported. This guide explains what MIDI is, what transcription can realistically do, and the steps to convert your own audio.
What MIDI is and why it is useful
MIDI (Musical Instrument Digital Interface) is not recorded sound. Instead of storing an audio waveform, a MIDI file stores a set of instructions: which note plays, at what pitch, when it starts, how long it lasts and how hard it is struck. Because the music is described as data rather than captured as audio, MIDI files are tiny and fully editable.
That editability is the whole point. Once a part exists as MIDI you can drag notes to fix a wrong pitch, quantize the timing, transpose the key, or swap the sound entirely by routing the same notes through a different virtual instrument. A line played on guitar can be reproduced on piano, strings or synth without re-recording anything.
What audio-to-MIDI transcription does
Audio-to-MIDI transcription analyzes a recording and estimates the notes it contains, then exports them as MIDI. Common uses include:
- Editing a melody or bassline after it was already recorded.
- Changing instruments or layering new sounds over an existing part.
- Feeding a notation program to produce sheet music or tablature.
- Sketching ideas quickly or building sampler and remix material.
Steps to convert audio to MIDI
Using the free Audio to MIDI converter takes a few steps:
- Open the converter and upload your audio file (MP3, WAV, OGG, FLAC, M4A, MP4 and more).
- Start the conversion and wait for the transcription to finish.
- Download the resulting MIDI file.
- Open it in your DAW or notation software to edit, re-instrument or export.
If you also need the recording in another format, you can Convert to MP3 separately, and a Song Key Finder can help you confirm the key before you transpose.
Frequently asked questions
Can I convert MP3 to MIDI?
Yes. Upload an MP3 to the Audio to MIDI converter and it will analyze the recording and export the detected notes as a MIDI file. WAV, FLAC, OGG, M4A and other formats work the same way.
Is audio-to-MIDI conversion accurate?
Automatic transcription is approximate. It works best on clean, monophonic or simple material such as a single melody, vocal line or bassline. Dense polyphonic mixes with many overlapping instruments are much harder to transcribe accurately, so expect to clean up the result by hand.
Will the MIDI sound like the original recording?
No. MIDI stores notes and timing, not the original audio, so it plays back through whatever instrument you assign. The point is that you can edit those notes and choose a new sound rather than reproduce the exact recording.
Do I need to install software or sign up?
No. The converter runs in your browser with no account and no installation. Files up to 500 MB are supported.
How do I get the best results?
Start with the cleanest source you have and isolate a single part if possible. A solo instrument, vocal or bassline transcribes far better than a full mix. After exporting, fine-tune the notes in your DAW or notation editor.