Convert WebM to MP4
Free, private, and entirely in your browser — no upload, no account, no watermark.
The converter opens with MP4 already chosen as the output. Just drop your WebM file and convert — nothing uploads.
How it works
Tap the button above — MP4 is pre-selected as the output format.
Your file stays on your device. Wait for the green “Engine ready” banner on first use.
Click Convert, then download your MP4 file straight to your device.
About WebM, and why convert to MP4
WebM is Google’s web-first container: VP9 or VP8 video with Opus audio. Chrome saves screen recordings as WebM, and websites love it because it is small and royalty-free. Video editors, Apple devices and many sharing apps do not love it back.
If a recording or download arrived as WebM and your editor, phone or platform will not take it, MP4 is the fix. The same picture and sound, in the container everything accepts.
Quality guidance for this conversion
Re-encoding VP9 to H.264 costs a little quality no matter what, so use Balanced quality at Original resolution — that keeps the loss hard to notice. WebM files are already small, so do not expect a big size drop; the payoff is that the file now opens everywhere.
Frequently asked questions
My Chrome screen recording is WebM — will this fix it?
Yes, that is the most common case. Chrome records to WebM by default, and converting to MP4 makes the recording editable and shareable.
Does the sound survive?
Yes, the Opus audio is converted to AAC along with the video.
Will I lose quality?
A little — VP9 to H.264 is a real re-encode. At Balanced quality and Original resolution the difference is barely visible.
Is the MP4 smaller?
Not necessarily. WebM is already efficient, so the file may come out about the same size. Compatibility is the win.