WMV (Windows Media Video) is a legacy Microsoft format that fewer and fewer devices support. Converting to MP4 future-proofs old recordings, screen captures, and corporate video archives.
Convert WMV to MP4 – Free Online WMV to MP4 Converter
Why convert WMV to MP4?
- Play old WMV recordings on Macs, Linux, mobile, and modern smart TVs.
- Convert legacy corporate training videos into a portable, shareable format.
- Reduce file size — modern MP4 codecs are far more efficient than WMV9.
What is the difference between WMV and MP4?
| WMV | MP4 | |
|---|---|---|
| Container origin | Microsoft's ASF wrapper, late 1990s Windows Media push | ISO standard container, actively maintained |
| Typical codecs inside | WMV9 video with WMA audio | H.264/H.265 video with AAC audio |
| Platform reach | Windows-centric; support shrinking even there | Every OS, browser, phone, and TV |
| DRM | Supported copy protection (PlaysForSure era); blocks conversion | Plain MP4 files carry no DRM |
| Best for | Nothing current — a format to migrate away from | The destination for that migration |
Does converting WMV to MP4 lose quality?
Every WMV goes through a complete transcode on the way to MP4 — WMV9 video and WMA audio have no seat in the target container — so this conversion behaves the same for every file: decode, re-encode, remux. Resolution and frame rate come through unchanged, and since most WMVs are standard definition or 720p, the modern codec handles them with ease.
File size usually drops, often substantially, because H.264 achieves the same picture in roughly half the bits WMV9 needs. If your WMVs are screen recordings (very common — Windows capture tools defaulted to WMV for years), the sharp text and flat colors compress especially well. Old interlaced footage from camcorder transfers is the one category that can show comb lines on motion; that artifact is inherited from the source.
One hard limit: DRM-protected WMVs — purchased or corporate-locked files from the PlaysForSure/Silverlight era — cannot be converted by any tool, because the streams themselves are encrypted. Only unprotected recordings and exports convert.
What can go wrong converting WMV to MP4?
- The conversion fails on a video I bought years ago — Purchased WMVs from 2000s stores are usually DRM-encrypted, and no converter can legally or technically open them. Only DRM-free files (your own recordings, exports) will convert.
- Fast motion shows horizontal comb lines in the MP4 — The source was interlaced — typical for camcorder-to-PC transfers of that era. The lines were always in the file; a desktop tool with a deinterlace filter can clean them up if it matters.
- My old corporate training video exceeds the 50 MB free limit — Long WMV lectures often pass 50 MB despite modest resolution. Split the recording into parts before uploading, or run a batch of full-length files through a desktop converter.
How to convert WMV to MP4
- Upload your WMV file using the area above.
- MP4 is preselected as the target format.
- Click Start and wait for the conversion to finish.
- Download your converted MP4 file.