What is Windows Media Player's Extension?

By Beth Bartlett

Microsoft's audio and video utility, the Windows Media Player, has been a major force in the growth of portable sound file technology. The native formats for the player are Windows Media Audio and Windows Media Video; these .wma and .wmv extensions are compatible with nearly every media device and computer operating system on the market, while the newest Advanced Systems Format (.asf) is for the combination of compressed audio and video.

Playing Windows Media Files on the Computer

To play .wma or .wmv files on your computer, you will need Windows Media Player, which is available for free download directly from Microsoft. The player automatically plays both .wma and .wmv files, as well as other file types. Microsoft also makes Windows Media Player for other operating systems, including Mac and Linux, so music fans need not own a Windows system in order to hear their tunes.

On the iPod

Windows Media files must be converted from .wma format to .mp3 format to play on Apple's mobile devices. Converting the .wma or .wmv files requires both iTunes and the Windows Media Player for Apple; each program is available via free download. If a Windows Media file is copy-protected, it cannot reliably be converted for iPod use; doing so is also a violation of copyright laws.

Other Portable Media Players

While Apple requires the conversion of .wma files, most other media players, including those made by RCA, Creative and Coby, are programmed to automatically recognize the Windows Media Audio format. For Windows Media Video files, check the instruction manual or manufacturer's website for compatibility and details.

Using Older Versions

Since Microsoft has cycled through several versions of Windows Media Player, there are devotees of older versions who prefer the simpler interface and workability. Others who use older operating systems may find that an earlier release works better on their computers. Fortunately, these older versions of Windows Media Player can be found on the Internet and downloaded; these players will still play .wma files, but may not have as many features as newer versions.


The Advanced Systems Format, or .asf file, is becoming more common as people use Windows Media Player for more than just music. The .asf file can contain both .wma and .wmv formats in sync for seamless playback of videos with sound. Earlier versions of Windows Media Player don't support .asf; the .asf files can be played back only on releases of Windows Media Player 7 through the current version.