MP4 to WebM Converter
Create open, web-ready WebM videos from MP4. Free and private, right in your browser.
Why convert MP4 to WebM?
WebM is an open, royalty-free video format designed for the web and supported by Chrome, Edge, Firefox and current versions of Safari. Many sites offer a WebM version alongside MP4 in their HTML5 video tags, and some platforms and tools ask for WebM specifically.
Smushify encodes WebM with the VP8 video codec and Vorbis audio, which are light enough to run reliably in the browser and play back almost everywhere WebM is supported.
How to convert MP4 to WebM
Drop your MP4 files above with WebM selected. Pick a quality and maximum width, then click Convert All. Conversion runs on your device, so longer videos take a while; keep the tab open until it finishes. Output is capped at 1920 pixels wide to stay within browser memory limits.
Frequently asked questions
Is WebM smaller than MP4?
It depends on the settings. File size is mostly controlled by the quality and width you choose, so lower either one for a smaller video.
How long does conversion take?
Video encoding is demanding and runs on your own computer or phone. Short clips take seconds; long, high-resolution videos can take several minutes.
Are my files uploaded anywhere?
No. Smushify converts everything inside your browser using WebAssembly. Your files are never sent to a server, so it is safe for private photos, client work and unreleased videos.
Can I convert many files at once?
Yes. Drop in as many files as you like, use "Format for all" and "Quality for all" to set every file in one go, then click Convert All and Download All.
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