WMV to MP4 Converter
Convert WMV to MP4 free — no upload, no signup
To convert WMV to MP4, drop your WMV video into the box below and click Convert. Fylo converts with ffmpeg running inside your browser, so nothing is uploaded and there's no signup or watermark. Windows Media videos become H.264 MP4 that plays on Macs and phones.
Drop videos here
or tap to browse · paste with Ctrl+V · add many at once
Your files never leave your device
If the video already uses codecs that fit the new format, Fylo repackages it instantly with no quality loss.
Advanced
How to convert WMV to MP4
Add your WMV videos
Drag and drop WMV files into the box or tap to choose them. The converter engine (about 31 MB) downloads once, the first time you convert.
Choose quality (optional)
Balanced quality suits most videos. If the codecs already fit MP4, Fylo repackages the file instead of re-encoding it, with no quality loss.
Convert and download
Click Convert, then download each MP4 file or all of them as one ZIP.
Why convert WMV to MP4?
WMV files from old Windows cameras, Movie Maker projects and corporate archives won't play on iPhones, Macs or most websites. MP4 fixes that.
What happens when you convert WMV to MP4?
Fylo decodes the WMV (including WMV9/VC-1) and re-encodes it to H.264 with AAC audio. The MP4 is often smaller than the WMV and plays everywhere.
How does Fylo convert WMV to MP4?
Fylo reads the WMV with ffmpeg compiled to WebAssembly and writes H.264 (x264, constant quality CRF 23) with AAC audio, plus the faststart flag for instant web playback. WMV's usual codecs (WMV 7/8/9 (VC-1)) can't go into MP4 as-is, so the video is re-encoded. Speed depends on your device: short phone clips take seconds, while on our slow test PC a 2-minute 1080p video took about 10 minutes. Only the first video and audio track are kept, and the original resolution is preserved unless you pick 1080p, 720p or 480p under Advanced.
What's the difference between WMV and MP4?
WMV (Windows Media Video) is a family of Microsoft video codecs introduced in 1999, stored in the Advanced Systems Format (ASF) container together with WMA audio. WMV 9 was standardised as VC-1 and used on HD DVD and early Blu-ray discs.
MP4 (MPEG-4 Part 14) is a container format standardised in 2001 and based on Apple's QuickTime file structure. A container holds separately compressed video and audio streams plus metadata such as subtitles, chapters and cover art. Most MP4s use H.264 video and AAC audio; newer files may use H.265 (HEVC) or AV1.
Learn more: WMV format guide · MP4 format guide
| Property | WMV | MP4 |
|---|---|---|
| Developed by | Microsoft | MPEG (ISO/IEC 14496-14) |
| Introduced | 1999 | 2001 |
| Typical video codecs | WMV 7/8/9 (VC-1) | H.264, H.265/HEVC, AV1 |
| Typical audio codecs | WMA | AAC, MP3 |
| Plays in web browsers | No | Yes — every browser |
| Compatibility | Windows Media Player, Windows apps; poor on Mac and phones | Universal: phones, TVs, editors, social media |
| Best for | Old Windows software and PowerPoint presentations | Sharing, uploading, streaming, editing |
Frequently asked questions
Can a Mac play WMV?
Not in QuickTime. Converting to MP4 is the simplest solution.
Does it work with DRM-protected WMV?
No. Copy-protected Windows Media files can't be converted.
Is my WMV file uploaded to a server?
No. Fylo runs ffmpeg, the same engine used by professional video tools, compiled to WebAssembly inside your browser. Your WMV file is read directly from your device and never sent anywhere.
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