WebM to MP4 Converter
Turn web videos and screen recordings into MP4 any app opens.
Free · No upload · No sign-up · No watermark
How to convert WebM to MP4
- 01
Open your WebM file
Drop the WebM — a screen recording, a download or any other video.
- 02
Keep MP4 selected
It's already chosen. Pick a part or a smaller size if you like.
- 03
Convert and download
The picture is converted to H.264 and the sound to AAC on your device.
Why use Cutlia for this
For apps that skip WebM
Many phones, TVs and editing apps don't open WebM; an H.264 MP4 works in nearly all of them.
VP8, VP9 and AV1
Whatever the WebM holds, the MP4 gets H.264 at the same size and frame rate.
Screen recordings
Recordings from browser-based screen recorders convert right where they were made, without an upload.
Frequently asked questions
Is WebM to MP4 lossless?
No: VP8, VP9 and AV1 are re-encoded to H.264 — the codec MP4 players expect — in high quality. Sound is converted to AAC.
Why won't my WebM open on my phone or in my editor?
WebM is made for web browsers. Photo apps, many TVs and video editors expect MP4 with H.264, which is what you get here.
Is my video uploaded to a server?
No. Cutlia processes your video directly in your browser using WebAssembly and your device's hardware. The file never leaves your computer or phone, so it stays completely private.
Is it really free?
Yes. Cutlia is free to use with no account, no trial and no watermark on your export. The site is paid for by the ads on it, and your files never leave your device.
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Each is this converter with the format already picked — and it still opens any video.