How it works
MP4 to MP3 / WAV runs on this page, in browser memory. The file you choose is never sent to a server: it is read through the File API, processed locally and handed back as a download.
In three steps
- Choose a file from your device, or drag it onto the drop area.
- Adjust the options on the right, if the tool has settings.
- Press “Process locally” and download the result.
What it takes and what it returns
This tool accepts MP4, M4V, MOV and produces MP3, WAV. The work is done by Web Audio API + lamejs.
Real limits
These limits come from what a browser can do safely, not from a paid plan:
- A WAV track cannot exceed 256 MB; choose MP3 for long files.
- Input formats depend on the codecs your browser can decode.
What it does not do
Decoding depends on the browser's codecs. AAC in MP4 works in current mainstream browsers; exotic formats may be refused.
Common questions
Do my files reach a server?
No. Processing happens in browser memory. The network is used only to download the application's libraries, and your file's contents are not part of those requests.
Which formats does MP4 to MP3 / WAV accept?
It accepts MP4, M4V, MOV and produces MP3, WAV.
Do I need an account?
No. The tool works without an account and without installing anything during the free pilot.
Does it work on a phone?
Yes, in current browsers. Very large files can exceed the memory a phone has available, in which case the job stops with a clear message.