MP4 to WebM Converter
WebM is an open format made for the web, supported by all current browsers.
Runs in your browser · No uploads
Drag & drop an MP4 video here
or
MP4 or M4V videos · converted to WebM
Your files stay on your device. Nothing is uploaded.
Your browser is too old to run this tool. Please update it, or use a current version of Chrome, Edge, Firefox or Safari.
- Nothing leaves your device
- No server-imposed size limits
- No sign-up, no watermark
- Free
How to convert MP4 to WebM
- Choose your MP4 video.
- The output is set to WebM; choose the quality used if the video has to be re-encoded.
- Press Convert and download the WebM file.
Good to know
- The video is re-encoded to VP9 (or VP8) and the sound to Opus.
- When the video and sound can be copied into the new format as they are, they are not re-encoded: no quality loss, and very fast.
- Best in current Chrome and Edge; recent Safari and Firefox work too.
Your videos stay on your device
Everything happens in your browser. Your videos are never uploaded, and this site's security policy blocks the page from sending files anywhere.
Frequently asked questions
Is there a size limit?
No server-imposed file size limits. The practical limit is your device's memory: several gigabytes work on most computers.
Are my videos uploaded?
No. They are converted in your browser and never sent anywhere.