MP4 to WebM
Convert MP4 video to WebM (VP9).
MP4 to WebM re-encodes video to VP9/Opus WebM for web delivery. Conversion runs locally with ffmpeg.wasm.
Frequently Asked Questions
Are my media files uploaded?
No. Processing uses ffmpeg.wasm in your browser. Files never leave your device. The first run downloads a ~25MB media engine from a CDN.
Why is the first run slow?
The media engine (~25MB) downloads once per browser session from a CDN, then stays cached.
Which formats work?
Most MP4/WebM/MOV and common audio formats your browser and ffmpeg.wasm can decode. Exotic codecs may fail.