Convert MP4 to WebM without uploading it
MP4 is the most widely supported video container in the world, playable on every phone, browser, TV and editing app. WebM is an open container built for the web, used by screen recorders and browsers. Switch from one to the other on your own device: drop the file, click convert, download.
Drop your files here
or click to choose files. Drop several to process them all with the same settings.
Why convert MP4 to WebM? Because it plays everywhere without extra software, while iPhones, TVs and most editing apps do not support it well. MP4 files usually contain H.264 or HEVC video with AAC audio; WebM expects VP8, VP9 or AV1 video with Opus or Vorbis audio.
The codecs used by MP4 are not accepted by WebM, so the video is re-encoded on your device at a bitrate matched to the original. Your hardware encoder does the work, which is much faster than uploading.
WebM requires VP8, VP9 or AV1, so H.264 sources are always re-encoded. VP9 typically produces a file 20 to 30 percent smaller than H.264 at the same quality.
How to convert MP4 to WebM
- Drop the MP4 file. It is read straight from your disk. Nothing is uploaded, so there is no waiting and no file size cap.
- Keep WebM selected. Leave “maximum compatibility” on so the result plays everywhere, or turn it off to always copy the streams unchanged.
- Convert and download. Preview the result and save it. The original file is untouched.
Why use myownvid for this
Nothing is uploaded
The file is read straight from your disk and processed by your browser. There is no server, so there is nothing to leak, store or delete.
Faster than any upload
Your device’s hardware encoder does the work. No queue, no upload bar, no waiting for a download afterwards.
No watermark, no account
Every tool is free with no sign-up, no export cap, no resolution limit and no logo stamped on your video.
Presets that match real limits
Discord, WhatsApp, email, Reels: pick the destination and the settings are already right.
Questions people ask
Does converting MP4 to WebM lose quality?
The video has to be re-encoded, so a tiny amount of detail is traded away. The tool matches the original bitrate so the difference is very hard to notice.
How long does MP4 to WebM take?
Re-encoding typically runs at several times real-time speed on a recent laptop or phone with a hardware encoder. A five-minute clip is done in about a minute.
Is it really free with no upload?
Yes. The page is a static website and the conversion runs inside your browser using its built-in video engine. Your MP4 file never leaves your device, which is also why there is no watermark, no account and no size limit.
Can I convert several MP4 files?
One file at a time for now. After downloading, click “Start over with another file” and drop the next one. Batch conversion is on the roadmap.