WebM is an open video container form Google. It is a container for VP8/VP9/AV1 (video) and Vorbis/Opus (audio). VP9 is the latest format and offers 25-50% size reduction. While VP9 supported by most browsers, desktop video players lask support. You may download video player like VLC to play them. PS2PDF support compressing of WebM with VP8 and VP9. The main factor that relates video output quality to size in WebM compression is called CRF (Constant Rate Factor). CRF is a rate control factor (quality/file size) for VP8/VP9 encoders. Lower values of CRF produce larger output sizes but has higher quality. To reduce high-quality large file without loosing quality, you can use a slower Preset to compress it more.
Our free online WebM Video compressor allows you to compress WebM files without limitations. It is the fastest online free WebM video compressor on the web. You can compress a WebM video (.WebM) by setting Constant Rate Factor (a General Option) to ~21 and Preset to medium to get an amazing quality compressed WebM video.
Another way to compress WebM files is to resize them to a smaller size. You can use the Resize dropdown on Output Dimension section to select a Preset Resolotions such as 8k, 4K, 1080p, 720p, 480p, 360p, 240p, and other non-standard options to reduce WebM video width and height.
Or you can set WebM Video width and height relatively or independently. Setting relative is preferred if you want to keep the aspect ratio intact.
Most WebM videos you take from iPhones and Androids converted to .WebM format or .webm. These formats can be open using VLC Player . In fact, VLC can open almost any WebM video format and support Linux and MacOS platforms.
The default option is to install VLC player. On Ubuntu (Debian) you can run sudo apt-get install vlc. Make sure you have X11 installed.
Quick Time does not support .WebM file format. You will need to install VLC player to be able to view WebM video on MacOS.