Convert ASF to MP4
ASF and MP4 are both lossy, so converting compresses the file again and loses a little more detail.
They open in the converter with MP4 selected.
Browse filesFiles stay on your device.
What changes
Both formats are lossy. Converting decodes the file and compresses it again, so it loses a little more detail on top of what the original had already lost: the result is slightly worse than the file you started with.
The file size stays about the same.
Your browser may not be able to open ASF files, but the converter reads the file itself, so it can still convert it.
When it’s worth it
Choose MP4 for: Phones, websites, social networks, and TV. Small files for the quality, usually with H.264 or H.265 inside.
Stay with ASF for: Legacy Windows streaming files.
How to convert ASF to MP4
- Drop the ASF files on this page, or browse for them. Up to 200 at once.
- The converter opens with the files loaded and MP4 selected.
- Press Convert, then save each file or all of them as a ZIP.
Questions
Does converting ASF to MP4 lose quality?
A little. Both formats are lossy, so the file is compressed again and loses a bit more detail.
What is the MP4 format?
A container that holds a video track, one or more audio tracks and metadata, and nothing else: which codec sits inside is a separate question. H.264 or H.265 video with AAC audio is the combination almost everyone means by MP4.
What is the ASF format?
Advanced Systems Format, Microsoft's container for streaming media and the wrapper around WMV and WMA. It handles live streams and DRM well, and most non-Microsoft players don’t open it.
Are the files uploaded?
No. The file is opened in this tab, converted here and saved from here. There’s no account and no watermark.
How many files can be converted at once?
Up to 200 per batch and about 2 GB per file, within the memory this device has available.