Convert MP4 to WebM
WebM is the format browsers prefer for embedded video on the open web, and it usually produces smaller files than MP4 at a comparable quality. If you publish video on a website, that difference shows up directly in bandwidth and load time. The transcode uses your browser and its hardware acceleration where available, and the file is never uploaded.
Drop your files here to start converting
All conversions run locally in your browser — files are never uploaded
How to convert MP4 to WEBM
- Drag your MP4 files onto the page, or browse for them.
- Choose resolution, frame rate and bitrate if you want to override the defaults.
- Download the WebM files when the conversion finishes.
Frequently asked questions
Which browsers can play the WebM output?
Chrome, Firefox, Edge and Opera all play WebM. Recent versions of Safari support it as well.
Does the video get re-encoded?
Yes. Moving from MP4 to WebM changes the codec, so the frames are encoded again rather than copied.
Does it use my graphics hardware?
The converter relies on the WebCodecs API, which browsers can accelerate with the GPU. A recent Chrome or Edge gives the most reliable results.