WebM Overview
May 19, 2010

On, February 19, 2010 Google finalized its acquisition On2 Technologies, the creator of the VP8 codec, the codec used in WebM. (On2 (formerly The Duck Corporation) was also the company which created VP6, the video codec used in Adobe FLV2 format.)

On May 19/20 during the Google I/O Developers Conference in San Francisco, Google released a media format called WebM. This new format has commendable goal: to standardize video/audio playback on web and various devices.

What is WebM

  • Quoting from The WebM Project ( “WebM is an open, royalty-free, media file format designed for the web.”
  • WebM is not a codec, it is a container format like AVI, Quicktime, and WMV.
  • WebM format is derived from Matroska (aka: MKV) format.
  • WebM is a subset of MKV (Matroska). Not all MKV files are WebM files (see the next two line items)
  • WebM video is always encoded in VP8 (
  • WebM audio is always encoded in Vorbis (
  • WebM file extension is .webm
  • WebM supports multiple audio tracks.
  • WebM supports multiple subtitle tracks.
  • WebM supports multiple video tracks.


WebM is designed to be the prominent and de-facto video standard in the near future and is an attempt to arrive at an open and royalty-free standard video format that is supported across the board without requiring a plug-in. Since Google owns YouTube, which hosts perhaps more than half of the most used videos on the web, this goal is realistic.

  • It can be expected that others browser will support WebM in the near future, without requiring any plug-in.
  • With the backing and push from Google, WebM has a real potential to be the video standard in the very near future.  WebM is gaining support from Mozilla, Microsoft, and Opera.
  • Google has released the WebM as an open standard making is possible for anyone to implement WebM encoders and decoders, as well as making the VP8 an open-format, answering pleas from the community such as this one:

How to Create WebM files

Wildform, the company behind Flix has released a free WebM encoder, which you can download from The free download also include DirectShow filters so you can actually play webm files right now.

Or see this list: for other encoders.

How to play WebM files

  • On Window, Wildform Flix includes DirectShow filters required to play WebM files on Windows Media Player.
  • Opera Lab also has a build which supports WebM playback.
  • On Windows and MAC browser, download the latest Chromium build from
    Tips: You can also open and play a WebM file in Chrome browser by dragging a WebM file onto a Chrome browser that suports WebM.
  • Firefox Nightly build (http://nightly.mozilla.ord/webm/) might soon support it.

How to embed WebM files on webpages

WebM video can be embedded using the HTML5 <video> tag.
The MIME type for WebM is video/x-webm.

<video width="450" height="256">
   <source src="/videos/redcliff450.webm" type="video/x-webm"></source>

Note: Opera Labs Has A Slightly different example on their page (

<video controls="controls">
   <source src="video.webm" type='video/webm; codecs="vorbis,vp8"'>
   <p><a href="video.webm">Download the video</a>.</p>

Expect things to stadadize one WebM gains footing.


Sample WebM Video

To see a sample WebM video, click here.