EN

Convert MP4 to WebM

Convert MP4 videos to WebM, the open format for web pages, with VP9 video and Opus audio.

Your files never leave your device. Everything runs in your browser.

How it works

  1. Add your videosDrop the files; the target format is already set.
  2. Wait a momentMost files finish in seconds, the progress bar shows the rest.
  3. DownloadDownload the converted videos one by one or as a ZIP.

Video for web pages

WebM with VP9 video is often smaller than H.264 at the same quality, which makes it a good choice for background videos and clips embedded in web pages. All modern browsers play it with the HTML5 video element. The converter re-encodes the video to VP9 and the audio to Opus with your device's encoder.

For the widest compatibility, offer both formats on your site: WebM first and MP4 as a fallback.

Tip for background videos

Turn on Remove audio for silent background loops; the file gets smaller and browsers allow muted autoplay.

About MP4

MP4 is the most widely supported video format. With H.264 video and AAC audio it plays on practically every device and platform.

About WebM

WebM is an open video format designed for the web, with VP8, VP9 or AV1 video and Opus audio. Browsers play it natively.

Frequently asked questions

Is WebM smaller than MP4?

Often yes at the same quality, because VP9 compresses more efficiently than H.264.

Are my videos uploaded?

No. The conversion runs in your browser and the files stay on your device.

Is there a file size limit?

No fixed limit. Very large files depend on your device's memory.

Will the quality drop?

Not when only the container changes. When re-encoding is needed, the quality is kept high.

Which browser works best?

Current Chrome and Edge support the most formats. Safari and Firefox work for most files.