OctoolyWhy convert MP4 to WebM?
WebM is a good choice for video on your own website: it is open, royalty-free and, with VP9, usually smaller than MP4 at the same quality.
How to convert MP4 to WebM
- Drop your MP4 file in the box above, or click to choose it.
- Check the options and click the button. Your browser does the conversion.
- Download your WebM. Nothing was uploaded.
What is MP4?
MP4 with H.264 video and AAC audio is the most compatible video format there is. It plays on phones, TVs, browsers, WhatsApp, Instagram and every video editor.
What is WebM?
WebM is the open video format of the web (VP8, VP9 or AV1 video with Opus audio). Browsers handle it well, but iPhones, PowerPoint and many editors don't.
Frequently asked questions
Is it really free?
Yes. No sign-up, no watermark and no limit on how many files you convert. The site is paid for by ads.
Is my video uploaded anywhere?
No. The conversion runs inside your browser, on your own computer. The file never leaves your device, not even to our servers.
Is there a file size limit?
There is no upload limit, because nothing is uploaded. Very large files (several GB) depend on your computer's memory.
Will I lose quality?
The video is re-encoded to VP9. On High quality the difference is very hard to see, and the file is often smaller.
Which browsers work?
Google Chrome and Microsoft Edge on a computer work best. They have the video encoders the converter needs.