WebM to MP4
Drop a WebM from a screen recorder or a download and get an MP4 that opens in any editor, on any phone and on every upload site.
Your file stays on your device. Nothing is uploaded.
WebM to MP4 in three steps
Drop your WebM
Up to 500 MB.
Convert
The video is re-encoded to H.264 and the sound to AAC.
Download the MP4
It plays on phones, in editors and in browsers.
Where WebM files come from
WebM is the format browsers use for web video. Screen recorders, browser extensions and some download sites save WebM, usually with VP8 or VP9 video and Opus sound.
Plenty of video editors and phones don't take those codecs, so the WebM has to be re-encoded, not just renamed. This tool converts the video to H.264 and the sound to AAC, the pair every app and site accepts.
Re-encoding runs on your own device, inside the browser, so it takes longer than a remux: expect a minute or more for a few minutes of video. The file never leaves your computer.
Frequently
Asked Questions
Can I just rename .webm to .mp4?
No. The video inside a WebM uses different codecs, so a renamed file won't play in most apps. It needs to be converted.
Does it keep the sound?
Yes. The audio is converted to AAC inside the MP4.
Why does it take a while?
Every frame is re-encoded on your device, in the browser, using one processor core. A computer is faster than a phone.
Is my file uploaded?
No. It's processed in your browser, on your own device, and never leaves it.