ASF Files
ASF files are media containers that compress multiple audio or video streams. They are perfect for streaming online across a range of different bandwidths — helping make your videos more accessible to the masses.
Learn more about their pros and cons and how to open them.

What is an ASF file?
An ASF (Advanced Systems Format) file is a container file that holds several types of data, like video, audio, and metadata, in a single file. Microsoft developed the file type specifically for sharing and storing media.
ASF files are similar to MPEG-4 files, which are also used for storing video and audio for online playback. They can store audio data or combine video data, audio data, and metadata.
While the ASF file extension saves media in the ASF format, the WMA and WMV extensions are more popular alternatives. If the ASF container stores audio, it saves as a Windows Media Audio (WMA) file. If the ASF file stores video, it saves as a Windows Media Video (WMV) file. Users can compress audio and video data using different containers.
History of the ASF file.
Microsoft developed the Advanced Systems Format between 1996 and 1998 for streaming media. It was formerly known as “Advanced Streaming Format” and “Active Streaming Format” before settling on the current name.
Since its rollout in February 1998, it has been the file type of choice for Windows Media Player. It was originally patented to only be compatible with Microsoft software.
However, it has since been able extended to Apple iTunes, where you can now convert ASF files for use on that platform.
How to use ASF files.
ASF files have multiple uses:
Metadata storage.
ASF files store essential metadata. This includes information related to the structure of the file, including video chapters, subtitles, and authors, which make it easier to find the right file when you need it.
Playback.
ASF files support file playback from different media servers, HTTP servers, and local storage devices, such as hard drives. They don’t affect how well these play, as this depends on things like bandwidth and device. However, they do ensure that video and audio can achieve the maximum quality possible, if bandwidth and the device allows.
Pros and cons of ASF files.
Pros.
- Available on a range of apps. ASF files make playback of great video and audio content possible on a wide range of apps and servers — ensuring your content is experienced to its full potential.
- Minimal buffering. They also support scalable audio, video, and data, allowing easy sharing of files over a wide range of bandwidths. This means that even if someone is viewing your content over a poor internet connection, they can still play it back with only minimal buffering.
What’s more, you can open and play an ASF file online before it finishes downloading.
Cons.
- Don’t specify the codec for playback. Because ASF files are containers, they only hold the structure of the audio and video content. This means they don’t specify which codec (the software that compresses or decompresses the video to determine file size) encodes the content, ready for playback.
- Vulnerable to corruption. WMA and WMV are usually the chosen codecs that are used to compress ASF files. However, if other filetypes are used, then this could potentially corrupt the file.
- Potentially lower quality. ASF files are also highly compressed, meaning the video quality may be lower than some other container formats. This is also the same with audio quality, which is also contained within an ASF file.
How to open a ASF file.
You can open an ASF file with several media players. Windows Media is the default video player software in Windows that supports ASF files. You can also open ASF files with the VLC media player in macOS and Linux, and with Penta Loop Playerxtreme Media Player in iOS.
How to open ASF in Windows Media Player.
To open an ASF file in Windows Media Player, just:
- Search for and open Windows Media Player from the start menu.
- Drag the ASF file into Windows Media Player and hit the play button to start or play the video or audio file.
How to open ASF in VLC.
To open an ASF file in VLC Media Player:
- Locate your ASF file in your folders.
- Double-click to open the file.
- Playback should begin automatically.
If you don’t have access to any of these, an alternative approach is to convert your ASF file to another format supported by your chosen media player.
How to create and edit a ASF file.
You can find free online video-making and editing tools to help you create and edit videos in the ASF file format. Or try creating and editing ASF files in Adobe Premiere Pro and Adobe Media Encoder. Media encoder can import ASF with the On2 VP6 video codec.
Discover which video file formats Adobe Premiere Pro supports.

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Is ASF better than MP4?
Does VLC support ASF?
Is ASF the same as WMV?
How do you convert an ASF to an MP4 file?
You can convert an ASF file to an MP4 file using Adobe Media Encoder. Simply:
- Choose “File” in the top left of your screen.
- Select your chosen ASF file and it will add to the queue.
- Click on the export preset of your choice.
- Choose MP4 as the output file and decide where it will be saved.
- Press start and the conversion will begin.
Learn more about similar file types to ASF.
AVI.
Microsoft developed AVI is the standard container format for its operating systems. Discover more about this flagship format and how it works.
OGG.
Perfect for storing audio, track listings, and artist information, OGG is a widely used audio file that could be the ideal choice for your next project. Learn more about it.
MP4.
MP4 files are among the most common forms of video file format. Explore why they’ve exploded in popularity for content creators looking to store video and audio.
MOV.
Apple’s MOV files are a popular video file type for Mac devices. See how they work when storing films, TV shows, and short video clips.
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