ASF is a legacy Microsoft container that may not open cleanly in modern browsers, phones, TVs, upload forms, and editors. MP4 is accepted by more devices and apps.
WMV refers to Windows Media Video codecs commonly stored in an ASF container.
What this converter actually supports
Convertr uses the deployed FFmpeg toolchain for published audio and video routes. A container such as MP4, MOV, MKV, AVI, or WebM can hold different codecs, so the file extension alone does not guarantee that a particular player will accept the contents.
Convert WMV to MP4 for current browsers, phones, televisions, and editing software.
The public upload limit is 1 GB. Convertr does not reduce dimensions, duration, resolution, or output quality merely to manage worker load.
Quality and format limits
Keep the original dimensions and frame rate unless you intentionally need a smaller result. Remuxing compatible streams avoids re-encoding; changing codecs is lossy, so repeated conversions should be avoided.
DRM and uncommon WMV profiles can prevent decoding, and the extension does not describe the audio stream.
Published WMV inputs
These links come from the active conversion catalog, not from a generic list of possible formats.
Check that the file opens in its original application, is not encrypted or DRM-protected, and really matches its extension. A damaged header, unsupported internal codec, missing linked asset, or mislabeled file can fail even when WMV is generally supported. Try a different published target only when it fits your goal; changing the extension by hand does not convert the file.