Video
Turn your MP4 files into M4A in seconds. Everything happens in your browser: nothing is uploaded to any server.
Drag your files here
Or paste them with Ctrl+V. They never leave your device.
At equal quality it takes slightly more space than a WebM with VP9. As M4A it sounds good at a small size and opens on iPhone, Android and Windows.
MP4 is the most widespread video container; here it comes out with H.264 video and AAC audio, the most compatible combination.
Strengths: It plays on any phone, TV, browser or social network without installing anything.
Limits: At equal quality it takes slightly more space than a WebM with VP9.
M4A is AAC audio in an MP4 container: the format of iTunes, iPhone voice memos and many podcasts.
Strengths: Good quality at a small size, with tags and artwork, and it opens on Apple, Android and Windows.
Limits: Some old players or editing programs only accept MP3 or WAV.
No. The MP4 to M4A conversion runs entirely in your browser, with code downloaded from this site and executed on your device. You can check it in the Network tab of the developer tools or by going offline after the page loads.
Yes: in the options set the start and end time, for example from 1:30 to 2:45, and only that clip is extracted.
Up to 2 GB and 3 hours of video on desktop; on mobile, 500 MB and 30 minutes (AVI: 1 GB and 1 hour on desktop). If it is over, you are told before it starts and can trim it.
Yes. Drop as many MP4 files as you like: several are converted at the same time, depending on your processor cores, and when they finish you can download each M4A or all of them in a ZIP.