How to convert MP4 to WEBM
- Add your .MP4 file - drop it in the box above or click to browse.
- Convert it to .WEBM in a few seconds.
- Download your new .WEBM file.
What to expect
- MP4 and WEBM share no codecs, so every conversion is a full re-encode - expect a small quality loss compared to the source.
- VP9 encoding is slow; a 10-minute 1080p clip can take 20-60 minutes on a typical PC at default quality settings.
- Subtitles embedded in the
MP4are dropped silently - WEBM has no standard subtitle container track.
Frequently asked questions
Does converting MP4 to WEBM lose quality?
Yes, always. Codec incompatibility forces a re-encode, which degrades the signal slightly with each pass. Start with the highest-quality
MP4 you have and use a conservative quality setting.Why is there no audio in my converted WEBM?
AAC audio from
MP4 cannot be copied directly into WEBM and must be re-encoded to Opus. In FFmpeg, include -c:a libopus -b:a 128k in your command to add the audio track.Does WEBM play in all browsers?
Chrome, Firefox, and Edge support VP9 WEBM natively. Safari has supported VP9 since version 16 (macOS Ventura / iOS 16, 2022), but older devices may not play it.
Is a WEBM file smaller than MP4?
At the same visual quality, VP9 WEBM is typically 20-40% smaller than H.264 MP4, which is why it is popular for web delivery.
Programs that convert MP4: Freemake Video Converter · Free Studio · MediaCoder · SUPER · WinX Video Converter · Miro Video Converter · XMedia Recode · Wondershare Video Converter
