WebM is an open format built for the web: efficient VP9 video and Opus audio that play in Chrome, Firefox and Edge. Convert your MP4 to WebM without uploading it anywhere.
Drag & drop, click to browse, or paste
MP4, MOV, WebM, MKV
Runs fully in your browser. Your files are never uploaded.
Drop, paste or choose a MOV, MP4, WebM or MKV file. It stays on your device.
Pick MP4 for maximum compatibility or WebM for the web, and set the quality.
Conversion runs in your browser with hardware acceleration. Preview the result and save the file.
Your files are processed on your device and never uploaded to any server.
No account, no limits and no watermark on your results.
Runs at native speed in your browser and keeps working once the page has loaded.
You choose the settings - nothing is silently downscaled or recompressed.
Use WebM for videos embedded on your own website, where it is often smaller than H.264 at the same quality. Use MP4 for sharing with other people and apps.
Recent versions of Safari play WebM, but older devices and many video apps do not. Choose MP4 when you need maximum compatibility.
VP9 is often 20-40% more efficient than H.264 at the same quality, but results vary by video. Try the Smaller file quality option to shrink it further.
