How to use the ASF converter
- Choose a file. Drop an ASF file to convert it to something else, or any other video to convert it to ASF.
- Check "Convert to". The converter picks MP4 for ASF files and ASF for everything else; change it if you need something different.
- Adjust quality if you want a smaller or higher-quality file.
- Click Convert and download the result.
What is an ASF file?
ASF is the Microsoft container that holds Windows Media audio and video. A .wmv or .wma file is really an ASF file; some security cameras and old streaming tools save the generic .asf extension.
ASF is mainly used for old Windows Media streams and some CCTV systems. It plays on Windows Media Player and VLC.
ASF at a glance
| Full name | Advanced Systems Format |
|---|---|
| Type | Video |
| Created by | Microsoft, 1996 |
| Compression | Lossy |
| Typical codecs | WMV + WMA |
| Can be created here | Yes |
Pros and cons of ASF
Good
- Native on older Windows
Not so good
- Outdated
- No support on phones, Macs or browsers
Common ASF problems and fixes
An ASF from a camera will not play
Convert it to MP4.
Frequently asked questions
How do I open an ASF file?
ASF files play on Windows Media Player and VLC. If yours will not open, convert it to MP4 on this page; that format plays on any device.
How do I convert a file to ASF?
Drop any video on this page. "Convert to" is set to ASF automatically for files that are not ASF already.
Do I have to pay or sign up to use the ASF converter?
No. There is no account, no payment and no watermark. The only limit is 1 GB per file, set by what browsers can handle.
Are my files safe?
Yes. Files are converted locally in your browser and are never uploaded. When you close the page, nothing is left behind.
Is ASF lossy?
Yes, ASF normally uses lossy compression, which removes detail you are unlikely to notice to keep files small.