Convert MP4 to WEBM
WEBM (VP8 + Opus) is the open format built for the web. 100% local conversion.
Your files never leave your device
How to convert MP4 to WEBM
- 1
Upload the MP4
The video to optimize for the web.
- 2
Convert
VP8 video + Opus audio.
- 3
Download the WEBM
Ready for your site.
Why use this tool
Open format
No patents or licenses: the web's free standard.
Opus audio
The most efficient audio codec in its range.
For your website
Background videos and light clips without H.264 dependencies.
Private
The video never leaves your device: ffmpeg runs in your browser.
Frequently asked questions
VP8 or VP9?
We use VP8: on a single browser thread, VP9 would be painfully slow. VP8 balances quality, weight and conversion time well.
Where does WEBM play?
Chrome, Firefox, Edge and modern Safari. Keep the MP4 too for old devices and apps.
Is quality lost?
The conversion uses high-quality settings; the visual difference from the original is small.
Why is it slower than other conversions?
VP8 encoding costs more than copying streams — still much faster than VP9.