Convert WebM to MP4
Convert WebM screen recordings and downloads into MP4 that every player and editor accepts.
- Your WebM file never leaves your device
- No sign-up, no watermark, no daily quota
- Handles files up to about 900 MB — your browser's memory ceiling
What happens when you convert WebM to MP4
Converts WebM, the format browsers produce when recording, into MP4 for maximum compatibility. Video is re-encoded from VP8 or VP9 to H.264 at CRF 23 and audio to AAC at 128 kbps, with a fast-start index so it plays immediately when streamed.
Good for
- Making browser screen recordings playable in editors and on phones
- Uploading to platforms and apps that reject WebM
- Sharing with Apple hardware, where WebM support is inconsistent
Worth knowing
- VP9 sources may end up slightly larger as H.264, which is less efficient at the same quality.
- Alpha transparency, which WebM can carry, is not supported by MP4 and is flattened.
- A full re-encode, so expect it to take roughly as long as the clip itself on a typical laptop.
WebM to MP4, answered
How do I convert WebM to MP4?
Drop your WebM file into the box above (or click to browse), make sure MP4 is selected as the target format, press Convert, then download the result.
Is this WebM to MP4 converter really private?
Yes. The conversion runs entirely in your browser — your WebM file is never uploaded to any server, so nobody but you ever sees it.
Is converting WebM to MP4 free?
Completely free — no watermarks, no sign-up and no daily quota. Processing happens on your own device, so there are no server costs to pass on to you.
Can I convert multiple WebM files at once?
Yes — drop as many files as you like. Convert them individually or use "Convert all", then download everything as a single ZIP.