WebM
| Filename extension |
.webm |
|---|---|
| Internet media type |
video/webm, audio/webm |
| Developed by | Initially On2, Xiph, and Matroska; later Google |
| Initial release | May 18, 2010 |
| Latest release | v1.13.0 January 31, 2023 |
| Type of format | Container format |
| Container for | VP8/VP9/AV1 (video) Vorbis/Opus (audio) |
| Extended from | Limited subset of Matroska |
| Open format? | Yes |
| Free format? | Yes |
| Website | webmproject.org |
WebM is an audiovisual media file format. It is primarily intended to offer a royalty-free alternative to use in the HTML video and the HTML audio elements. It has a sister project, WebP, for images. The development of the format is sponsored by Google, and the corresponding software is distributed under a BSD license.
The WebM container is based on a profile of Matroska. WebM initially supported VP8 video and Vorbis audio streams. In 2013, it was updated to accommodate VP9 video and Opus audio. It also supports the AV1 codec.