About Midilace
Midilace is a single-purpose website: it turns one audio or video file into an editable MIDI file inside your browser. You choose a file, the browser estimates its notes and timing, and you download a standard .mid file you can open in any DAW.
What this site does
Exactly one thing. There is no account, no dashboard, no file history, and no editor. The homepage is the tool. The conversion runs on your own machine using JavaScript and WebAssembly that your browser downloads once, so the recording you select is never sent anywhere for processing.
Because the work happens locally, the output quality depends on your device and on the recording itself. Clear single-instrument material and melodies come out best. Dense mixes, drums, reverb, vocals, and background noise usually produce wrong or missing notes. Treat the result as a starting point and clean it up in your DAW.
Who runs it
Midilace is an independent project, built and maintained by one developer who wanted a converter that did not require signing up or handing a private recording to someone else's server. It is not a company, not a studio, and not affiliated with any of the open-source projects listed below.
If you have a question, a bug report, or a file that produced obviously wrong notes, the contact page explains how to reach the person who runs this site.
About the name
Midilace is the name of this website and this tool. It is not the real name of the person who runs the site, and it is not the name of a registered company.
Open-source components
Midilace is built on other people's work, and their licences are respected here:
- Media decoding uses ffmpeg.wasm, including
@ffmpeg/core0.12.10, which declares GPL-2.0-or-later. Its decoder file is delivered compressed and unpacked inside your browser. Read the GPL version 2 text. - Note estimation uses Spotify Basic Pitch (Apache-2.0).
- MIDI writing uses ToneJS/Midi (MIT).
What Midilace is not
It is not a stem splitter, a transcription service, or a way to recover a performance exactly. It does not store your files, and it cannot recover them for you afterwards. If a claim about accuracy matters to you, test the tool on your own material before relying on it.