MP4 to WebM
Drop an MP4 from almost every phone, camera app and editor export and get a WebM file you can use where MP4 won't open.
Your file stays on your device. Nothing is uploaded.
MP4 to WebM in three steps
Drop your MP4
Up to 500 MB.
Convert
The file is re-encoded in your browser.
Download the WebM
Ready to play, edit or upload.
MP4 vs WebM, in short
MP4 is the most widely supported video format: phones, browsers, editors and every upload site play it.
WebM is the web's open video format, usually with VP8 or VP9 video. Browsers, screen recorders and some download sites save it, but many editors and phones won't open it.
The video is re-encoded to VP8 video with Opus sound, which every browser plays. That runs on your own device, in the browser, so it takes a while for longer videos.
Frequently
Asked Questions
Does converting MP4 to WebM lose quality?
It's re-encoded once, at good quality settings. Most people won't see a difference.
Is the sound kept?
Yes. The audio track comes along with the video.
How long does it take?
It depends on the length: re-encoding in the browser uses one processor core, so expect a minute or more per minute of video.
Is my file uploaded?
No. It's processed in your browser, on your own device, and never leaves it.