Video & audio · runs locally
Convert video formats
MP4, WebM and MKV — the three containers that cover phones, the web and archives. Swap between them without a desktop app.
- 1Drop a video
Almost any common format is readable.
- 2Pick the target
MP4 (H.264) is the universal choice. WebM is web-native but slower to encode here. MKV is a friendly container for archiving.
- 3Choose a quality preset
Smaller (CRF 28), Balanced (23) and Sharper (18) cover most jobs; Custom exposes the full CRF range. Advanced adds encoder speed and audio bitrate.
Questions people actually ask
Why can't I convert to AVI or WMV?
Those formats are comfortably past their usefulness for the web, and the engine here is kept lean on purpose. MP4 has been the sane answer since 2008.
What's the best format for a website?
MP4/H.264 for compatibility everywhere, WebM as a smaller second source if you want to serve the best to modern browsers.
Why is WebM so slow?
This build uses libvpx (VP8) for WebM, which is much slower than x264 in the browser engine. MP4 finishes first; WebM trades time for a web-native file. The page warns you before you start.